abundar

A RAG di que a segunda acepción de abundar é

2. Dar argumentos ou razoamentos para demostrar que se está de acordo cun determinado criterio, opinión etc. O secretario abundou nas palabras do presidente.

E o  dicionario de protocéltico di que

*bu-n-do- 'proclaim, give notice' [Vb]

GOlD: OIr. ad-boind; a-t-Mis [2s Subj.]; ad-buib [3s Fut.]; at-bobuid [3s Pret.]

BRET: OBret. dogurbonnue [3s Pres. Subj.] PIE: *bhewdh _'be awake' (IEW: 150-152)

COGN: Skt. b6dhati 'wakes, notices', OE bodian 'announce', Gr. peuthomai 'give notice'

ETYM: OIr. ad-boind is from *ad-bund-o-, while the preterite at-bobuid < *uss-bu-bud-. OBret. dogurbonnue presupposes *to-ufor-bunde-. The meaning and etymological connection of the OBret. form dogurbonnue are not fully ascertained, cf. KPV 237. If OIr. ad-boind is indeed from PIE *bhewdli - 'be awake', we must assume a complex evolution of meaning, as in Gr.peuthomai and OE bodian: 'be awake' > 'make oneself noticed' > 'give notice'. The same PIE root may be attested in OIr. ro-bud [u and 0 m] 'a notice beforehand', W rhybudd [m] 'warning, caution' < PCelt. *fro-bowdo- < PIE *bhowdho_. REF: KPV 236f, LIV 82f, LP 347, LEIA B-69, Delamarre 81, McCone 1991: 43, Schumacher 2000: 180

Parece que proclamar, dar noticia do protocéltico bundo, convertido en Old Irish en ad-boind ten moito que ver co abundar 2 da RAG que dá noticia do acordo con outra postura.