PLA'INLY, adverb With a level surface. [Little used.] 1. Without cunning or disguise. 2. Without ornament or artificial embellishment; as, to be plainly clad. 3. Frankly; honestly; sincerely; as, deal plainly with me. 4. In earnest; fairly. 5. In a manner to be easily seen or comprehended. Thou shalt write on the stones all the words of this law very plainly Deuteronomy 27:8. 6. Evidently; clearly; not obscurely. The doctrines of grace are plainly taught in the Scriptures.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI