Old English *steortian, *stiertan, Kentish variants of styrtan "to leap up" (attested only in Northumbrian past participle sturtende), from Proto-Germanic *stert- (source also of Old Frisian stirta "to fall, tumble," Middle Dutch sterten, Dutch storten "to rush, fall," Old High German sturzen, German stürzen "to hurl, throw, plunge"). According to Watkins, the notion is "move briskly, move swiftly," and the Proto-Germanic word is from PIE root *ster- (1) "stiff."

From "move or spring suddenly," sense evolved by c. 1300 to "awaken suddenly, flinch or recoil in alarm," and by 1660s to "cause to begin acting or operating." Meaning "begin to move, leave, depart" (without implication of suddenness) is from 1821. The connection probably is from sporting senses ("to force an animal from its lair," late 14c.). Transitive sense of "set in motion or action" is from 1670s; specifically as "to set (machinery) in action" from 1841.

Related: Started; starting. To start something "cause trouble" is 1915, American English colloquial. To start over "begin again" is from 1912. Starting-line in running is from 1855; starting-block in running first recorded 1937.

late 14c., "an involuntary movement of the body, a sudden jump," from start (v.). Meaning "act of beginning to move or act" is from 1560s. Meaning "act of beginning to build a house" is from 1946. That of "opportunity at the beginning of a career or course of action" is from 1849. Paired with finish (n.) from at least 1839. False start first attested 1850.

also startup, 1550s, "upstart," from verbal phrase (attested from c. 1200 in sense "rise up;" 1590s as "come suddenly into being"); see start (v.) + up (adv.). Meaning "action of starting up" is from 1845. See start (v.) + up (adv.).

1919 (implied in kick-starter), "method of starting an internal combustion engine (of a motorcycle) by pushing down a lever with the foot," from kick (n.) + start (n.). Figurative sense of "take a course of action that will quickly start a process" is by 1995.

also jumpstart, "to start a car engine using battery booster cables," by 1970; see jump (n.) + start (v.). The sense of jump is that in the jump-spark ignition system, attested from 1883 in gas-lighting, from c. 1902 as a common way to start an automobile; hence also jumper "wire used to cut out ('jump over') part of a circuit or to close a gap," a sense attested from 1901 in telegraphy. Related: Jumpstarted; jumpstarting. Figurative use by 1975. Jump-leads "jumper-cables" is from 1969; jumper-cables from 1961.

also re-start, "start again," 1845, from re- "again" + start (v.). Related: Restarted; restarting. As a noun from 1881, "a fresh start."

c. 1400, stertour "instigator; one who starts," agent noun from start (v.). Mechanical sense is from 1875. For starters "to begin with" is 1873, American English colloquial. Starter home is from 1976; starter set is from 1946, originally of china.

1550s, "one newly risen from a humble position to one of power, importance, or rank, a parvenu," also start-up, from up (adv.) + start (v.) in the sense of "jump, spring, rise." As an adjective from 1560s. Compare the archaic verb upstart "to spring to one's feet," attested from c. 1300.

c. 1300, " move agitatedly, run to and fro" (intransitive), also "caper, romp, skip; leap, jump;" from Old English steartlian, from the source of start (v.) + frequentative suffix -le (as in topple, jostle, fizzle, etc. Sense of "move suddenly in surprise or fear" first recorded 1520s. Transitive meaning "frighten suddenly" is from 1590s. The word retains more of the original meaning of start (v.). Related: Startled; startling; startlingly. As a noun from 1714.

Proto-Indo-European root meaning "stiff."

It forms all or part of: cholesterol; redstart; starch; stare; stark; stark-naked; start; startle; starve; stere; stereo-; stern (adj.); stork; strut; torpedo; torpid; torpor.

It is the hypothetical source of/evidence for its existence is provided by: Greek stereos "solid," sterizein "to support," sterphnios "stiff, rigid," sterphos "hide, skin;" Sanskrit sthirah "hard, firm," Persian suturg "strong;" Lithuanian storas "thick," strėgti "to become frozen;" Old Church Slavonic trupeti, Lithuanian tirpstu, tirpti "to become rigid;" Old Church Slavonic strublu "strong, hard," staru "old" (hence Russian stary "old"); Old English starian "to stare," stearc "stiff, strong, rigid," steorfan "to die," literally "become stiff," styrne "severe, strict."