present participle of thumb

The act by which something is thumbed.

(in combination) Having some specific type of thumb.

simple past tense and past participle of thumb

Of a book, etc.: showing signs of frequent or heavy use; worn; well used.

A general guideline, rather than a strict rule; an approximate measure or means of reckoning based on experience or common knowledge. / (attributive, usually hyphenated) Approximated, guesstimated.

plural of thumbnail

Third-person singular simple present indicative form of thumbnail

(anatomy, informal) The fleshy portion, opposite the nail, of the first segment (first phalange) of the human thumb.

A screw that can be turned with the thumb and fingers. / An instrument of torture used to crush the fingers. / (figuratively) A weakness that can be taken advantage of.