Hel"met (?), n. [OF. helmet, a
dim of helme, F. heaume; of Teutonic origin; cf. G.
helm, akin to AS. & OS. helm, D. helm,
helmet, Icel. hjālmr, Sw. hjelm, Dan.
hielm, Goth. hilms; and prob. from the root of AS.
helan to hide, to hele; cf. also Lith. szalmas, Russ.
shleme, Skr. çarman protection. √17. Cf.
Hele, Hell, Helm a helmet.] 1.
(Armor) A defensive covering for the head. See
Casque, Headpiece, Morion, Sallet, and
Illust. of Beaver.
2. (Her.) The representation of a
helmet over shields or coats of arms, denoting gradations of rank by
modifications of form.
3. A helmet-shaped hat, made of cork, felt,
metal, or other suitable material, worn as part of the uniform of
soldiers, firemen, etc., also worn in hot countries as a protection
from the heat of the sun.
4. That which resembles a helmet in form,
position, etc.; as: (a) (Chem.) The
upper part of a retort. Boyle. (b)
(Bot.) The hood-formed upper sepal or petal of some
flowers, as of the monkshood or the snapdragon.
(c) (Zoöl.) A naked shield or
protuberance on the top or fore part of the head of a bird.
Helmet beetle (Zoöl.), a leaf-
eating beetle of the family Chrysomelidæ, having a
short, broad, and flattened body. Many species are known. --
Helmet shell (Zoöl.), one of many
species of tropical marine univalve shells belonging to Cassis
and allied genera. Many of them are large and handsome; several are
used for cutting as cameos, and hence are called cameo shells.
See King conch. -- Helmet shrike
(Zoöl.), an African wood shrike of the genus
Prionodon, having a large crest.
