0 the short, thick finger on the side of your hand that makes it possible to hold and pick things up easily
1 to stand near the edge of a road and hold out your hand with the thumb raised as a signal for a vehicle to stop and take you somewhere:
2 the short finger that is at an angle to the other fingers:
3 if an idea, project, etc. gets the thumbs down, it is not approved:
4 to be approved:
The controversial merger got the thumbs up from investors.
I sucked my thumb until I was seven.
Follow with the eyes keeping the head still - three times with each hand and three times with the hands together, thumbs crossed.
From this standpoint, the evolutionarily advantaged functions of divided attention, upright bipedal ambulation and opposable thumbs can be seen as vulnerable.
I suspect this a book that will be heavily thumbed over on library shelves by people with a wide range of interests.
Information retrieval by means of the computer's search engine takes much less time than thumbing through the pages of an alphabetic dictionary.
