run-in
UK[ˈrʌn ɪn]US[ˈrʌn ɪn]
n
An argument or disagreement.
n
A period of time before an event when someone or something is tested or prepared.
Morpheme Breakdown
run
in
run
to move quickly
in
inside, into
Etymology
The compound noun 'run-in' is a relatively modern English formation, originating in the late 19th century from the phrasal verb 'to run in'. Its literal sense, derived from the combination of 'run' (to move swiftly) and 'in' (to the interior), initially referred to the act of moving something into a place or position, such as running a new engine at low speed to properly seat its parts. This mechanical sense logically extended to mean a preparatory or testing period before full operation. The more abstract meaning of a 'disagreement' or 'altercation' evolved from the figurative idea of people 'running into' each other, not physically, but in a clash of opinions or wills, capturing the sudden, often confrontational nature of such encounters.
Analysis
Structure: run (to move quickly) + in (inside, into)
- run: From Old English rinnan, iernan (to flow, to run). A Germanic verb root meaning to move swiftly on foot.
- in: From Old English in (in, into, within). A Germanic preposition/adverb indicating position or direction.
Examples
He had a run-in with his neighbor over the property line.
The new employee is still in the run-in phase, learning the company's procedures.
During the run-in to the election, the candidate focused on local issues.