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Studies.AkinboFwangwar2026

Akinbo and Fwangwar (2026): Iconicity and expressiveness of grammatical tones targeting ideophones in Mwaghavul #

Mwaghavul derives verbs from ideophones by a segmentally null verbaliser with two lexically selected allomorphs, whose only exponents are the tunes M and M-H. A singular verb bears M on every syllable, or M on every nonfinal syllable and H on the final one. A pluractional verb doubles the ideophone and bears M on every syllable of the reduplicant and H on every syllable of the base, so corresponding syllables never agree in tone, an iconic disharmony. The derived verbs occur wherever underived verbs do and stay expressive, against the claimed inverse relation between grammatical integration and expressiveness. The paper classifies the verbaliser as replacive-dominant grammatical tone and derives its realisation in Optimality Theory from constraints anchoring the verbaliser's tones to the edges of roots.

The printed verbs fit replacive dominance and no other dominance type, so the magnitude iconicity the ideophones carry in their lexical tones is lost in their verbs. The three tableaux, built from the dataset's ideophones under one constraint set, select the printed verbs exactly under the rankings with R-ANCH-Hᵥ ≫ R-ANCH-Mᵥ ≫ L-ANCH-Hᵥ and MAX-Tone below both M anchors. Two dominations the paper states, L-ANCH-Mᵥ ≫ R-ANCH-Mᵥ and L-ANCH-Hᵥ ≫ MAX-Tone, are not needed.

Main statements #

Implementation notes #

TODO #

References #

The verbaliser as replacive-dominant grammatical tone #

The two lexically selected allomorphs of the verbaliser, VBZ₁ with the tune M and VBZ₂ with the tune M-H.

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      The tune of a verbaliser on a single host: M spreading over every syllable, or M-H anchored at the right edge.

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        The verbaliser an ideophone selects, read off its singular verb: VBZ₁ when the verb is level M.

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          The singular verb of a trigger of dominance type d with verbaliser v: the tune applied to the ideophone's syllables.

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            The pluractional verb of a trigger of dominance type d: VBZ₂ on the doubled ideophone, each of its tones on its own root, M on the reduplicant and H on the base.

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              theorem AkinboFwangwar2026.fits_iff (d : Tone.Dominance) :
              (∀ i ∈ Mwaghavul.ideophones, i.verb = Option.map (fun (x : Verbalizer) => singular d x i) (verbalizer i) ∧ i.pluractional = pluractional d i) ↔ d = Tone.Dominance.replacive

              The printed verbs fit replacive dominance and no other type of [Rol18]'s typology: the singular verb is the selected verbaliser's tune applied to the ideophone, and the pluractional verb VBZ₂ on the doubled ideophone.

              The verbaliser overwrites the magnitude iconicity of lexical tone: wùlàʃ ‘wide open’ and wúláʃ ‘wide open of small thing’ differ only in tone and have the same verbs.

              The descriptive generalisations #

              theorem AkinboFwangwar2026.verb_melodies (i : Mwaghavul.Ideophone) :
              i ∈ Mwaghavul.ideophones → ∀ v ∈ i.verb, v = List.map (fun (x : Tone.TRN) => Tone.TRN.M) i.tones ∨ v = List.map (fun (x : Tone.TRN) => Tone.TRN.M) i.tones.dropLast ++ [Tone.TRN.H]

              Every singular verb has M on every syllable, or M on every nonfinal syllable and H on the final one.

              Which melody a singular verb has is lexical: wùlàʃ ‘wide open’ and bɨ̀ʃɔ̀l ‘shabbily dressed’ have the same tones and select different verbalisers.

              theorem AkinboFwangwar2026.pluractional_eq (i : Mwaghavul.Ideophone) :
              i ∈ Mwaghavul.ideophones → i.pluractional = List.map (fun (x : Tone.TRN) => Tone.TRN.M) i.tones ++ List.map (fun (x : Tone.TRN) => Tone.TRN.H) i.tones

              Every pluractional verb has M on every syllable of the reduplicant and H on every syllable of the base, whichever melody its singular verb has.

              theorem AkinboFwangwar2026.pluractional_disharmonic (i : Mwaghavul.Ideophone) :
              i ∈ Mwaghavul.ideophones → List.Forall₂ (fun (x1 x2 : Tone.TRN) => x1 ≠ x2) (List.take i.tones.length i.pluractional) (List.drop i.tones.length i.pluractional)

              Corresponding syllables of a pluractional verb's reduplicant and base never agree in tone, the disharmony that depicts distinguishable identity.

              Inputs and constraints #

              The morphemes of a derived verb: the ideophonic root, doubled into a reduplicant and a base in a pluractional verb, and the verbaliser.

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                  A form with syllable TBUs, tones, and the sponsoring morphemes.

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                    The input of an ideophone as the root m: one lexical tone for each run of identical tones, linked to every syllable of its run.

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                      The input of a verbaliser: its tones, floating.

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                        The constraints of the analysis: LEFT-ANCHOR and RIGHT-ANCHOR for the verbaliser's M and H ((22)), and MAX-Tone ((23)).

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                          def AkinboFwangwar2026.instReprCon.repr :
                          Con → ℕ → Std.Format
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                            The roots of a form, the morphemes sponsoring its syllables.

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                              def AkinboFwangwar2026.BearsTone {u : Form} (c : Autosegmental.Candidate u) (t : Tone.TRN) (i : Fin u.lower.length) :

                              Syllable i bears the verbaliser's tone t.

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                                instance AkinboFwangwar2026.instDecidableBearsTone {u : Form} (c : Autosegmental.Candidate u) (t : Tone.TRN) (i : Fin u.lower.length) :
                                Decidable (BearsTone c t i)
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                                LEFT-ANCHOR-Tᵥ and RIGHT-ANCHOR-Tᵥ ([Fin09b]): the verbaliser's t corresponds to the edge e of a root. One violation for each syllable between a root's edge and the nearest syllable bearing t, on the root where they are fewest, and one for every syllable when no root bears t.

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                                  The tones on the syllables of a candidate, left to right.

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                                    The M verbaliser and an unreduplicated ideophone #

                                    wùlàʃ ‘wide open’ with VBZ₁: one lexical L linked to both syllables, the verbaliser's M floating.

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                                      The candidates (24a)–(24e): (wùlàʃ)₁ M₂, (wùlàʃ)₁, (wù)₁(lāʃ)₂, (wū)₂(làʃ)₁, and (wūlāʃ)₂.

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                                          The tableau selects the spreading of M exactly when MAX-Tone is below both M anchors. It does not rank L-ANCH-Mᵥ against R-ANCH-Mᵥ, which the paper reads off it.

                                          The M-H verbaliser and an unreduplicated ideophone #

                                          The candidates (25a)–(25g): (háŋláɣáp)₁, (hāŋlā)₂(ɣáp)₁, (háŋláɣáp)₃, (hāŋlāɣāp)₂, (hāŋlā)₂(ɣáp)₃, (hāŋ)₂(láɣáp)₃, and (hāŋ)₂(lá)₁(ɣáp)₃.

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                                              The tableau selects M then H exactly under R-ANCH-Hᵥ ≫ R-ANCH-Mᵥ ≫ L-ANCH-Hᵥ and R-ANCH-Mᵥ ≫ MAX-Tone. It does not rank L-ANCH-Mᵥ against R-ANCH-Mᵥ either.

                                              The M-H verbaliser and a reduplicated ideophone #

                                              jàlpàt ‘hanging loose’ doubled into a reduplicant and a base, each with its own lexical L, with VBZ₂.

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                                                The candidates (26a)–(26g): (jàlpàt)₁(jàlpàt)₂, (jàl)₁(pāt)₃(jàl)₂(pát)₄, (jāl)₃(pàt)₁(jàl)₄(pàt)₂, (jālpāt)₃(jálpát)₄, (jāl)₃(pát)₄(jàlpàt)₂, (jālpāt jāl)₃(pát)₄, and (jāl)₃(pàt jàl)₁(pát)₄.

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                                                    The tableau ranks no two constraints on its own: it selects M on the reduplicant and H on the base exactly when MAX-Tone is below a left anchor, a right anchor, and one of R-ANCH-Mᵥ and L-ANCH-Hᵥ.

                                                    The ranking #

                                                    A ranking selects the printed verbs: the spreading of M over the root in the first tableau, M then H in the second, and M on the reduplicant with H on the base in the third.

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                                                      The tableaux select the printed verbs exactly under the rankings with R-ANCH-Hᵥ ≫ R-ANCH-Mᵥ ≫ L-ANCH-Hᵥ and MAX-Tone below both M anchors.

                                                      Neither L-ANCH-Mᵥ ≫ R-ANCH-Mᵥ nor L-ANCH-Hᵥ ≫ MAX-Tone, both of which the paper states, is needed: the ranking R-ANCH-Hᵥ ≫ R-ANCH-Mᵥ ≫ L-ANCH-Mᵥ ≫ MAX-Tone ≫ L-ANCH-Hᵥ reverses both and selects the printed verbs.

                                                      The paper's ranking, L-ANCH-Mᵥ and R-ANCH-Hᵥ ≫ R-ANCH-Mᵥ ≫ L-ANCH-Hᵥ ≫ MAX-Tone, selects the printed verbs.

                                                      The winners surface as the printed verbs wūlāʃ, hāŋlāɣáp, and jālpāt-jálpát.

                                                      Morphosyntactic integration #

                                                      theorem AkinboFwangwar2026.derived_verbs_integrated (row : Datum) :
                                                      row ∈ Examples.all → row.feature? "verb" = some "underived" → ∃ row' ∈ Examples.all, row'.feature? "verb" = some "derived" ∧ row'.feature? "construction" = row.feature? "construction"

                                                      Every construction attested with the underived verb of (11) is attested with the derived verb of (12): tense, focus, serial verbs, negation.