from
The Collaborative International Dictionary of English v.0.48
Thumb \Thumb\, n. [OE. thombe, thoumbe, [thorn]ume, AS.
[thorn][=u]ma; akin to OFries. th[=u]ma, D. duim, G. daumen,
OHG. d[=u]mo, Icel. [thorn]umall, Dan. tommelfinger, Sw.
tumme, and perhaps to L. tumere to swell. [root]56. Cf.
{Thimble}, {Tumid}.]
The short, thick first digit of the human hand, differing
from the other fingers in having but two phalanges; the
pollex. See {Pollex}.
[1913 Webster]
Upon his thumb he had of gold a ring. --Chaucer.
[1913 Webster]
{Thumb band}, a twist of anything as thick as the thumb.
--Mortimer.
{Thumb blue}, indigo in the form of small balls or lumps,
used by washerwomen to blue linen, and the like.
{Thumb latch}, a door latch having a lever formed to be
pressed by the thumb.
{Thumb mark}.
(a) The mark left by the impression of a thumb, as on the
leaves of a book. --Longfellow.
(b) The dark spot over each foot in finely bred black and tan
terriers.
{Thumb nut}, a nut for a screw, having wings to grasp between
the thumb and fingers in turning it; also, a nut with a
knurled rim for the same perpose.
{Thumb ring}, a ring worn on the thumb. --Shak.
{Thumb stall}.
(a) A kind of thimble or ferrule of iron, or leather, for
protecting the thumb in making sails, and in other work.
(b) (Mil.) A buckskin cushion worn on the thumb, and used to
close the vent of a cannon while it is sponged, or
loaded.
{Under one's thumb}, completely under one's power or
influence; in a condition of subservience. [Colloq.]
[1913 Webster]