Cucumber \Cu"cum*ber\ (k?`k?m-b?r, formerly kou"k?m-b?r), n.[OE. cucumer, cocumber, cucumber, fr. L. cucmis, gen. cucumeris; cf. OF. cocombre,F. concombre.]

(Bot.) A creeping plant, and its fruit, of several species of the genus Cucumis, esp. Cucumis sativus, the unripe fruit of which is eaten either fresh or picked. Also, similar plants or fruits of several other genera. See below.

Bitter cucumber (Bot.), the Citrullus or Cucumis Colocynthis. See Colocynth.

Cucumber beetle. (Zo["o]l.)
   (a) A small, black flea-beetle (Crepidodera cucumeris), which destroys the leaves of cucumber, squash, and melon vines.
   (b) The squash beetle.

Cucumber tree.
   (a) A large ornamental or shade tree of the genus Magnolia (M. acuminata), so called from a slight resemblance of its young fruit to a small cucumber.
   (b) An East Indian plant (Averrhoa Bilimbi) which produces the fruit known as bilimbi.

Jamaica cucumber, Jerusalem cucumber, the prickly-fruited gherkin (Cucumis Anguria).

Snake cucumber, a species (Cucumis flexuosus) remarkable for its long, curiously-shaped fruit.

Squirting cucumber, a plant (Ecbalium Elaterium) whose small oval fruit separates from the footstalk when ripe and expels its seeds and juice with considerable force through the opening thus made. See Elaterium.

Star cucumber, a climbing weed (Sicyos angulatus) with prickly fruit.

Source: Webster's Revised Unabridged Dictionary (1913)