du´al|ly

du|al «DOO uhl, DYOO-», adjective, noun.

–adj.

1. composed or consisting of two parts; double; twofold: »

The automobile had dual controls, one set for the learner and one for the teacher. The third and fourth boys…quickly became inseparable and were the dual delight of their father (Newsweek).

2. of two; showing two: »

the dual law which accounts for negative and positive electricity.

3. Grammar. (in certain languages including Old English) designating a number category signifying two persons or things: »

the dual number in Greek, a dual verb form.

–n. Grammar.

1. the dual number: »

Many languages have three numbers: singular, dual, and plural. Dual refers to two of a kind. In such a system, plural applies to three or more (Henry A. Gleason).

2. a word in the dual number.

╂[< Latin duālis < duo two]

–du´al|ly, adverb.