v. 竖指头；用拇指翻（thumb的ing形式）

Thumb \Thumb\, v. t. [imp. & p. p. {Thumbed}; p. pr. & vb. n.
{Thumbing}.]
1. To handle awkwardly. --Johnson.

2. To play with the thumbs, or with the thumbs and fingers;
as, to thumb over a tune.

3. To soil or wear with the thumb or the fingers; to soil, or
wear out, by frequent handling; also, to cover with the
thumb; as, to thumb the touch-hole of a cannon.

He gravely informed the enemy that all his cards had
been thumbed to pieces, and begged them to let him
have a few more packs. --Macaulay.