THUMB
THUM, n. The short thick finger of the human hand, or the corresponding member of other animals. [The common orthography is corrupt. The real word is thum.]
THUMB
THUM, v.t. To handle awkwardly; to play with the fingers; as, to thum over a tune.
1. To soil with the fingers.
THUMB
THUM, v.i. To play on with the fingers.