Webster’s Revised Unabridged Dictionary · 1913
Yea
Yea (yā or yē; 277), adv. [OE. ye, ya, ȝe, ȝa, AS. geá; akin to OFries. gē, iē, OS., D., OHG., G., Dan. & Sw. ja, Icel, jā, Goth. ja, jai, and probably to Gr. ἧ truly, verily. √188. Cf. Yes.]
1. Yes; ay; a word expressing assent, or an affirmative, or an affirmative answer to a question, now superseded by yes. See Yes.
Let your communication be yea, yea; nay, nay. Matt. v. 37.
2. More than this; not only so, but; — used to mark the addition of a more specific or more emphatic clause. Cf. Nay, adv., 2.
I therein do rejoice, yea, and will rejoice. Phil. i. 18.
☞ Yea sometimes introduces a clause, with the sense of indeed, verily, truly. "Yea, hath God said, Ye shall not eat of every tree of the garden?" Gen. iii. 1.
Yea, n. An affirmative vote; one who votes in the affirmative; as, a vote by yeas and nays.
☞ In the Scriptures, yea is used as a sign of certainty or stability. "All the promises of God in him are yea, and in him Amen." 2 Cor. i. 20.