1
British
: the final part of a race or racetrack
2
3
: something inserted as a substantial addition in copy or typeset matter
ran in; run in; running in; runs in
1
a
: to insert as additional matter
b
: to make (typeset matter) continuous without a paragraph or other break
2
somewhat old-fashioned
: 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
Cite this Entry
“Run-in.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/run-in. Accessed 20 Oct. 2026.
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