Elm \Elm\, n. [AS. elm; akin to D. olm, OHG. elm, G. ulme, Icel. almr, Dan. & Sw. alm, L. ulmus, and E. alder. Cf. Old.]

(Bot.) A tree of the genus Ulmus, of several species, much used as a shade tree, particularly in America. The English elm is Ulmus campestris; the common American or white elm is U. Americana; the slippery or red elm, U. fulva.

Elm beetle (Zo["o]l.), one of several species of beetles (esp. Galeruca calmariensis), which feed on the leaves of the elm.

Elm borer (Zo["o]l.), one of several species of beetles of which the larv[ae] bore into the wood or under the bark of the elm (esp. Saperda tridentata).

Elm butterfly (Zo["o]l.), one of several species of butterflies, which, in the caterpillar state, feed on the leaves of the elm (esp. Vanessa antiopa and Grapta comma). See Comma butterfly, under Comma.

Elm moth (Zo["o]l.), one of numerous species of moths of which the larv[ae] destroy the leaves of the elm (esp. Eugonia subsignaria, called elm spanworm).

Elm sawfly (Zo["o]l.), a large sawfly (Cimbex Americana). The larva, which is white with a black dorsal stripe, feeds on the leaves of the elm.

Source: Webster's Revised Unabridged Dictionary (1913)