Runaway

来自Big Physics

wiktionary

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run +‎  away


etymonline

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runaway (n.)

1540s (late 13c. as a surname), "one who flees or departs; a fugitive, deserter," from the verbal phrase run away "flee in the face of danger" (late 14c.); see run (v.) + away (adv.). From c. 1600 as "horse which bolts while being driven or ridden," later extended to railway trains, etc. The meaning "an act of running away" is from 1724.

As an adjective, "acting the part of a runaway, escaping from restraint or control," 1540s; in modern use especially of conditions, forces, reactions, etc., from 1925.