c. 1200, from Old English hleapan "to jump, spring clear of the ground by force of an initial bound; run, go; dance, leap upon (a horse)" (class VII strong verb; past tense hleop, past participle hleapen), from Proto-Germanic *hlaupanan (source also of Old Saxon hlopan, Old Norse hlaupa, Old Frisian hlapa, Dutch lopen, Old High German hlouffan, German laufen "to run," Gothic us-hlaupan "to jump up"), of uncertain origin, with no known cognates beyond Germanic; perhaps a substratum word.
First loke and aftirward lepe [proverb recorded from mid-15c.]
Transitive sense "pass over by leaping" is from early 15c. Leap-frog, the children's game, is attested by that name from 1590s ("Henry V"); figurative use by 1704; as a verb from 1872. To leap tall buildings in a single bound (1940s) is from the description of Superman's powers. Related: Leaped; leaping.
Dutch schrikkeljaar "leap year" is from Middle Dutch schricken "leap forward," literally "be startled, be in fear." The 29th of February is schrikkeldag. Danish skudaar, Swedish skottår are literally "shoot-year;" German schaltjahr is from schalten "insert, intercalate." The Late Latin phrase was annus bissextilis, source of the Romanic words; compare bissextile.
1590s, enterloper, "unauthorized trader trespassing on privileges of chartered companies," probably a hybrid from inter- "between" + -loper (from landloper "vagabond, adventurer," also, according to Johnson, "a term of reproach used by seamen of those who pass their lives on shore"); perhaps from a dialectal form of leap, or from Middle Dutch loper "runner, rover," from lopen "to run," from Proto-Germanic *hlaupanan "to leap" (see leap (v.)).
OED says Dutch enterlooper "a coasting vessel; a smuggler" is later than the English word and said by Dutch sources to be from English. General sense of "self-interested intruder" is from 1630s.
In support of this OED compares Old English uðleapan, "the technical word for the 'escaping' of a thief." However there is an Anglo-French aloper "run away from a husband with one's lover" (mid-14c.) which complicates this etymology; perhaps it is a modification of the Middle Dutch word, with Old French es-, or it is a compound of that and Middle English lepen "run, leap" (see leap (v.)).
The oldest Germanic word for "wedding" is represented by Old English brydlop (source also of Old High German bruthlauft, Old Norse bruðhlaup), literally "bride run," the conducting of the woman to her new home. Related: Eloped; eloping.
By normal evolution the Modern English form would be *gatelope, but the current spelling (first attested 1660s, not fixed until mid-19c.) is from influence of gauntlet (n.1) "a glove," "there being some vague association with 'throwing down the gauntlet' in challenge" [Century Dictionary].
Said to be so called from "the manner of its flight" [OED] "in reference to its irregular flapping manner of flight" [Barnhart], but the lapwing also flaps on the ground pretending to have a broken wing to lure egg-hunters away from its nest, which seems a more logical explanation. Its Greek name was polyplagktos "luring on deceitfully."