Boast, v. t.
1. To display in ostentatious language; to speak of with pride, vanity, or exultation, with a view to self-commendation; to extol. Lest bad men should boast Their specious deeds. Milton.
2. To display vaingloriously.
3. To possess or have; as, to boast a name. To boast one's self, to speak with unbecoming confidence in, and approval of, one's self; -- followed by of and the thing to which the boasting relates. [Archaic] Boast not thyself of to-morrow. Prov. xxvii.
3 other Webster entries under this spelling
Boast, v. i. [imp. & p. p. Boasted; p. pr. & vb. n. Boasting.]
1. To vaunt one's self; to brag; to say or tell things which are intended to give others a high opinion of one's self or of things belonging to one's self; as, to boast of one's exploits courage, descent, wealth. By grace are ye saved through faith; and that not of yourselves: .. not of works, lest any man should boast. Eph. ii. 8, 9.
2. To speak in exulting language of another; to glory; to exult. In God we boast all the day long. Ps. xiiv. 8
Syn. -- To brag; bluster; vapor; crow; talk big.
Boast, v. t.
1. (Masonry)
To dress, as a stone, with a broad chisel. Weale.
2. (Sculp.)
To shape roughly as a preparation for the finer work to follow; to cut to the general form required.
Boast, n.
1. Act of boasting; vaunting or bragging. Reason and morals and where live they most, In Christian comfort, or in Stoic boast! Byron.
2. The cause of boasting; occasion of pride or exultation, -- sometimes of laudable pride or exultation. The boast of historians. Macaulay.
Shades of meaning
Fernald has no entry of its own for boast; he lists it under ostentation.
He lists it without comment; the entries above explain its neighbors.