"to leave one's duty," late 14c., from Old French deserter (12c.) "leave," literally "undo or sever connection," from Late Latin desertare, frequentative of Latin deserere "to abandon, to leave, forsake, give up, leave in the lurch," from de- "undo" (see de-) + serere "join together, put in a row" (see series). Military sense is first recorded 1640s. Related: Deserted; deserting.
"wasteland," early 13c., from Old French desert (12c.) "desert, wilderness, wasteland; destruction, ruin," from Late Latin desertum (source of Italian diserto, Old Provençal dezert, Spanish desierto), literally "thing abandoned" (used in Vulgate to translate "wilderness"), noun use of neuter past participle of Latin deserere "forsake" (see desert (v.)).
Sense of "waterless, treeless region" was in Middle English and gradually became the main meaning. Commonly spelled desart in 18c., which is not etymological but at least avoids confusion with the other two senses of the word. Classical Latin indicated this idea with deserta, plural of desertus.
"suitable reward or punishment" (now usually plural and with just), c.1300, from Old French deserte, noun use of past participle of deservir "be worthy to have," ultimately from Latin deservire "serve well" (see deserve).
(1.) Heb. midbar, "pasture-ground;" an open tract for pasturage; a common (Joel 2:22). The "backside of the desert" (Ex. 3:1) is the west of the desert, the region behind a man, as the east is the region in front. The same Hebrew word is rendered "wildernes," and is used of the country lying between Egypt and Palestine (Gen. 21:14, 21; Ex. 4:27; 19:2; Josh. 1:4), the wilderness of the wanderings. It was a grazing tract, where the flocks and herds of the Israelites found pasturage during the whole of their journey to the Promised Land. The same Hebrew word is used also to denote the wilderness of Arabia, which in winter and early spring supplies good pasturage to the flocks of the nomad tribes than roam over it (1 Kings 9:18). The wilderness of Judah is the mountainous region along the western shore of the Dead Sea, where David fed his father's flocks (1 Sam. 17:28; 26:2). Thus in both of these instances the word denotes a country without settled inhabitants and without streams of water, but having good pasturage for cattle; a country of wandering tribes, as distinguished from that of a settled people (Isa. 35:1; 50:2; Jer. 4:11). Such, also, is the meaning of the word "wilderness" in Matt. 3:3; 15:33; Luke 15:4. (2.) The translation of the Hebrew _Aribah'_, "an arid tract" (Isa. 35:1, 6; 40:3; 41:19; 51:3, etc.). The name Arabah is specially applied to the deep valley of the Jordan (the Ghor of the Arabs), which extends from the lake of Tiberias to the Elanitic gulf. While _midbar_ denotes properly a pastoral region, _arabah_ denotes a wilderness. It is also translated "plains;" as "the plains of Jericho" (Josh. 5:10; 2 Kings 25:5), "the plains of Moab" (Num. 22:1; Deut. 34:1, 8), "the plains of the wilderness" (2 Sam. 17:16). (3.) In the Revised Version of Num. 21:20 the Hebrew word _jeshimon_ is properly rendered "desert," meaning the waste tracts on both shores of the Dead Sea. This word is also rendered "desert" in Ps. 78:40; 106:14; Isa. 43:19, 20. It denotes a greater extent of uncultivated country than the other words so rendered. It is especially applied to the desert of the peninsula of Arabia (Num. 21:20; 23:28), the most terrible of all the deserts with which the Israelites were acquainted. It is called "the desert" in Ex. 23:31; Deut. 11:24. (See JESHIMON.) (4.) A dry place; hence a desolation (Ps. 9:6), desolate (Lev. 26:34); the rendering of the Hebrew word _horbah'_. It is rendered "desert" only in Ps. 102:6, Isa. 48:21, and Ezek. 13:4, where it means the wilderness of Sinai. (5.) This word is the symbol of the Jewish church when they had forsaken God (Isa. 40:3). Nations destitute of the knowledge of God are called a "wilderness" (32:15, _midbar_). It is a symbol of temptation, solitude, and persecution (Isa. 27:10, _midbar_; 33:9, _arabah_).