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Definition of run-in
(Entry 1 of 2)
1 British : the final part of a race or racetrack
2 : altercation, quarrel
3 : something inserted as a substantial addition in copy or typeset matter
run in
verbran in; run in; running in; runs in
Definition of run in (Entry 2 of 2)
1a : to insert as additional matter
b : to make (typeset matter) continuous without a paragraph or other break
2 : to arrest for a usually minor offense
3 chiefly British : to break in (a new machine) gradually by careful operation
: to pay a casual visit
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Time Traveler for run-in
The first known use of run-in was in 1799
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