Runaway

Full definition of runaway

(plural runaways)

A person or animal that runs away or has run away; a person, animal, or organization that escapes limitations.Runaway children are vulnerable to criminal exploitation.

ShakespeareThou runaway, thou coward, art thou fled?
1556, Ralph Robinson, w, If any man of his owne heade and without leaue, walke out of his precint and boundes, taken without the princes letters, he is broughte againe for a fugitiue or a runaway with great shame and rebuke, and is sharpely punished.

1850, The Romance of the Electric Telegraph, On New Year's Day, 1850, a catastrophe, which it is fearful to contemplate, was averted by the aid of the telegraph. A collision had occurred to an empty train at Gravesend; and the driver having leaped from his engine, the latter started alone at full speed to London. Notice was immediately given by telegraph to London and other stations; and while the line was kept clear, an engine and other arrangements were prepared as a buttress to receive the runaway.
1886, John H. Cooper, Handling Grain in California, Runaways are rendered impossible, as the machine can be instantly stopped by means of a double brake connected with the driver's seat
1897, Editor American Machinist, Runaway Engines and Governors, We hear many ideas advanced as to the cause of engines running away, more especially in electric stations, while the wonder is that the runaways are so few.

(usually attributive) An object or process that is out of control or out of equilibrium.

1989, Gerald Appel, Winning market systems, On the chart, the start of a runaway is marked by a box
1993, June 15, An IS executive's worst nightmare, such runaways are a fact of life. Practically all large companies and organizations have experienced a runaway or are wrestling with a seriously botched project.
2000, F. Matteucci, The evolution of the Milky Way, The standard X-ray binary Cyg Xl, with a massive BH candidate, is a runaway, This could suggest that a SN explosion occurred. Cluster ejection to make a runaway can not be excluded although in the case of Cyg Xl, the progenitor runaway must have been a binary
2008, Francis Stoessel, Thermal safety of chemical processes, Where practicable, this passive measure reduces the consequences of a runaway.

The act of running away, especially of a horse or teams.There was a runaway yesterday.
An overwhelming victory.The home side won in a runaway.

This word is frequently used attributively, as in "runaway X" to mean "an X which has run away" or "an X which is out of control".