The Collaborative International Dictionary of English v.0.48:
Blemish \Blem"ish\, v. t. [imp. & p. p. Blemished; p. pr. &
vb. n. Blemishing.] [OE. blemissen, blemishen, OF. blemir,
blesmir, to strike, injure, soil, F. bl[^e]mir to grow pale,
fr. OF. bleme, blesme, pale, wan, F. bl[^e]me, prob. fr. Icel
bl[=a]man the livid color of a wound, fr. bl[=a]r blue; akin
to E. blue. OF. blemir properly signifies to beat one (black
and) blue, and to render blue or dirty. See Blue.]
1. To mark with deformity; to injure or impair, as anything
which is well formed, or excellent; to mar, or make
defective, either the body or mind.
Sin is a soil which blemisheth the beauty of thy
2. To tarnish, as reputation or character; to defame.
There had nothing passed between us that might
blemish reputation. --Oldys.