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.

HELMETED
Hel`met*ed, a.

Defn: Wearing a helmet; furnished with or having a helmet or helmet- shaped part; galeate.

HELMET-SHAPED
Hel"met-shaped` (, a.

Defn: Shaped like a helmet; galeate. See Illust. of Galeate.

HELMINTH
Hel"minth, n. Etym: [Gr. (Zoöl.)

Defn: An intestinal worm, or wormlike intestinal parasite; one of the
Helminthes.

HELMINTHAGOGUE
Hel*min"tha*gogue, n. Etym: [Gr. (Med.)

Defn: A vermifuge.

HELMINTHES
Hel*min"thes, n. pl. Etym: [NL., fr. Gr. (Zoöl.)