vacī : [f.] speech; word.

A.P. Buddhadatta Mahathera, Concise Pali-English and English-Pali Dictionary [available as digital version from Metta Net, Sri Lanka]

Vacī (˚ -- ) [the composition form of vaco] speech, words; rare by itself (and in this case re -- established from cpds.) and poetical, as at Sn 472 (yassa vacī kharā; expld at SnA 409 by "vācā"), 973 (cudito vacīhi=vācāhi SnA 574). Otherwise in cpds, like: -- gutta controlled in speech Sn 78. -- para one who excels in words (not in actions), i. e. a man of words J ii.390. -- parama id. D iii.185. -- bheda "kind of words," what is like speech, i. e. talk or language Vin iv.2; Miln 231 (meaning here: break of the vow of speech?); various saying, detailed speech, specification KhA 13; SnA 464, 466. See also vākya -- bheda & vācaŋ bhindati. -- viññatti intimation by language Vism 448; Miln 370; Dhs 637. -- vipphāra dilating in talk Miln 230, 370. -- samācāsa good conduct in speech M ii.114; iii.45; D iii.217. <-> Often coupled (as triad) with kāya˚ & mano˚ (=in deed & in mind; where vācā is used when not compounded), e. g. in (vacī) -- kamma (+kāya˚ & mano˚) deed by word M i.373, 417; iii.207; D iii.191, 245; ˚duccarita misbehaviour in words (four of these, viz. musāvāda, pisuṇā vācā, pharusā vācā, samphappalāpa A ii.141 D iii.52, 96, 111, 214, 217; Nd1 386; Pug 60; DhA i.23; iii.417; ˚sankhāraantecedent or requisite for speech M i.301; A iii.350; S iv.293; VbhA 167; Vism 531; ˚sañcetanā intention by word VbhA 144; ˚sucarita good conduct in speech A ii.141 (the 4: sacca -- vācā, apisuṇā vācā, saṇhā vācā, mantā bhāsā).

Pali-English Dictionary, TW Rhys Davids, William Stede,