Definition of break-in
(Entry 1 of 2)
1
: the act or action of breaking in
a rash of break-ins at the new apartment house
2
: a performance or a series of performances serving as a trial run
3
: an initial period of operation during which working parts begin to function efficiently
break in
verb
broke in; broken in; breaking in; breaks in
Definition of break in (Entry 2 of 2)
1
: to enter something (such as a building or computer system) without consent or by force
2a
: intrude
break in upon his privacy
b
: to interrupt a conversation
3
: to start in an activity or enterprise
breaking in as a cub reporter
1
: to accustom to a certain activity or occurrence
break in the new clerk
2
: to overcome the stiffness or newness of
break in a pair of shoes
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Merriam-Webster unabridged
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Time Traveler for break-in
The first known use of break-in was circa 1535
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