1550s, from Latin urgere "to press hard, push forward, force, drive, compel, stimulate," perhaps [de Vaan] from a PIE root *urgh- "to tie, bind" (source also of Lithuanian veržti "tie, fasten, squeeze," vargas "need, distress," vergas "slave;" Old Church Slavonic vragu "enemy;" Gothic wrikan "persecute," Old English wrecan "drive, hunt, pursue"), via a notion of "to weigh down on," hence "to insist, impel." The other possibility is that the PIE root is *ureg- "to follow a track." Related: Urged; urging.
mid-15c., from Old French urgent "pressing, impelling" (14c.), from Latin urgentem (nominative urgens), present participle of urgere "to press hard, urge" (see urge (v.)). Related: Urgently.
Old English wrecan "avenge," originally "to drive, drive out, punish" (class V strong verb; past tense wræc, past participle wrecen), from Proto-Germanic *wrekanan (source also of Old Saxon wrekan, Old Norse reka, Old Frisian wreka, Middle Dutch wreken "to drive, push, compel, pursue, throw," Old High German rehhan, German rächen "to avenge," Gothic wrikan "to persecute"), from PIE root *wreg- "to push, shove, drive, track down" (see urge (v.)). Meaning "inflict or take vengeance," with on, is recorded from late 15c.; that of "inflict or cause (damage or destruction)" is attested from 1817. Compare wrack (v.). Related: Wreaked; wreaking.
[clouds driven before the wind], c. 1300, rak, "movement, rapid movement," also "rush of wind, collision, crash," originally a northern word, possibly from Old English racu "cloud, storm" (or an unrecorded Scandinavian cognate of it), reinforced by Old Norse rek, *rak "wreckage, jetsam," or Old English wræc "something driven," both of which would be from Proto-Germanic *wrakaz, from PIE root *wreg- "to push, shove, drive" (see urge (v.)).
From late 14c. as "rain cloud." Often confused with wrack (n.) "destruction," especially in the phrase rack and ruin (1590s), which perhaps is encouraged in that case by the visual alliteration. Rack is "fragments of raggy clouds;" wrack is, in its secondary sense, "seaweed cast up on shore." Both probably come, ultimately, from the same PIE root, as does wreak.
Most Indo-European words for "personal enemy" cover also "enemy in war," but certain languages have special terms for the latter, such as Greek polemioi (distinct from ekhthroi), Latin hostis, originally "stranger" (distinct from inimicus), Russian neprijatel' (distinct from vrag). Russian vrag (Old Church Slavonic vragu) is cognate with Lithuanian vargas "misery" (see urge (v.)), and probably is related to Proto-Germanic *wargoz, source of Old Norse vargr "outlaw," hence "wolf;" Icelandic vargur "fox;" Old English wearg "criminal, felon;" which likely were the inspirations for J.R.R. Tolkien's warg as the name of a kind of large ferocious wolf in "The Hobbit" (1937) and "Lord of the Rings." Related: Enemies.
"urging to some course of conduct or action," 1580s, from French hortatoire and directly from Late Latin hortatorius "encouraging, cheering," from hortatus, past participle of hortari "exhort, encourage, urge, incite, instigate," intensive of horiri "urge, incite, encourage," from PIE root *gher- (2) "to like, want." Older in English is hortation (1530s), from Latin hortationem.