Meanings
- uncountableThe operating of a new engine (especially that of a motor vehicle) at less than its normal speed until proper working has been established.
[...] moreover, there are times of pressure when, to expedite deliveries, cars may be driven in what should otherwise be the running-in period at speeds that do them no good - and over long distances too.
1960 June, “British cars go by rail: I-The L.M.R. wins new Anglo-Scottish traffic”, in Trains Illustrated, page 3351 more example
For years past Pacific locomotives of all classes have worked between Kings Cross and Cambridge, […] both in order usefully to fill in gaps in their long-distance rosters, and also for running-in purposes after overhaul. Before the war the 7.18 a.m. slow from Kings Cross to Cambridge was a regular running-in turn for express locomotives stationed at Kings Cross shed.
1945 July and August, “The Why and The Wherefore: L.N.E.R. Pacifics at Cambridge”, in Railway Magazine, page 242
Translations
Finnish sisäänajo
- sisäänajooperation of a new engine for testing
French rodage
- rodageoperation of a new engine for testing
Italian rodaggio
- rodaggiooperation of a new engine for testing
Romanian rodaj
- rodajoperation of a new engine for testing
Spanish rodaje
- rodajeoperation of a new engine for testing
Cite this entry
running in. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/running%20in
“running in.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/running%20in. Accessed November 4, 2026.
WatkinsX Dictionary, s.v. “running in,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/running%20in.
Source: running in on Wiktionary, CC BY-SA 4.0.