Old English stridan (past tense strad, past participle striden), "to straddle, mount" (a horse), from Proto-Germanic *stridanan (source also of Middle Low German strede "stride, strive;" Old Saxon stridian, Danish stride, Swedish strida "to fight," Dutch strijden, Old High German stritan, German streiten "to fight, contend, struggle," Old Norse striðr "strong, hard, stubborn, severe").
The sense connection in the various Germanic forms is perhaps "strive, make a strong effort;" the senses having to do with walking and standing are found only in English and Low German. Meaning "to walk with long or extended steps" is from c. 1200. Cognate words in most Germanic languages mean "to fight, struggle;" the notion behind the English usage might be the effort involved in making long strides, striving forward.
"a step in walking," especially a long one, from Old English stride "a stride, a step," from the root of stride (v.). Compare Dutch strijd, Old High German strit, German Streit "fight, contention, combat," Swedish and Danish strid "combat, contention." From c. 1300 as a measure of distance roughly the length of a stride. Figurative meaning "advance rapidly, make progress" is from c. 1600. Of animals (especially horses) from early 17c. To take (something) in stride (1832), i.e. "without change of gait," originally is of horses leaping hedges in the hunting-field; figurative sense attested from 1902. To hit (one's) stride is from horse-racing. Jazz music stride tempo is attested from 1938. Meaning "a standing with the legs apart, a straddle" is from 1590s.
1805, agent noun from stride (v.).
c. 1200, "quarrel, fight, discord," from Old French estrif "fight, battle, combat, conflict; torment, distress; dispute, quarrel," variant of estrit "quarrel, dispute, impetuosity," probably from Frankish *strid "strife, combat" or another Germanic source (compare Old High German strit "quarrel, dispute"), related to Old High German stritan "to fight;" see stride (v.).
1560s, "spread the legs wide," probably an alteration of striddle (mid-15c.), frequentative of striden (see stride (v.)). Transitive sense "place one leg on one side of and the other on the other side of" is from 1670s. U.S. colloquial figurative sense of "take up an equivocal position, appear to favor both sides" is attested from 1838. Related: Straddled; straddling. The noun is first recorded 1610s.
late 14c., "a jump, a leap," from lope (v.). Sense of "long, bounding stride" is from 1809.