Definition of in
(Entry 1 of 11)
1a
—used as a function word to indicate inclusion, location, or position within limits in the lakewounded in the legin the summer
b
: into sense 1
went in the house
2
—used as a function word to indicate means, medium, or instrumentality written in pencilbound in leather
3a
—used as a function word to indicate limitation, qualification, or circumstance alike in some respectsleft in a hurry
b
: into sense 4a
broke in pieces
4
—used as a function word to indicate purpose said in reply
5
—used as a function word to indicate the larger member of a ratio one in six is eligible
in
adverbDefinition of in (Entry 2 of 11)
1a(1)
: to or toward the inside especially of a house or other building
come in
(2)
: to or toward some destination or particular place
flew in on the first plane
(3)
: at close quarters : near
play close in
b
: so as to incorporate
mix in the flour
—often used in combination built-in bookcases
c
: to or at an appropriate place
fit a piece in
2a
: within a particular place
especially
: within the customary place of residence or business
the doctor is in
b
: in the position of participant, insider, or officeholder
—often used with on in on the joke
c(1)
: on good terms
(2)
: in a specified relation
in bad with the boss
(3)
: in a position of assured or definitive success
d
: in vogue or season
e
of an oil well
: in production
f
: in one's presence, possession, or control
after the crops are in
g
: from a condition of indistinguishability to one of clarity
fade in
in for
: certain to experience
in for a rude awakening
in
adjectiveDefinition of in (Entry 3 of 11)
1a
: that is located inside or within
the in part
b
: that is in position, operation, or power
the in party
c
: inside sense 2
2
: that is directed or bound inward : incoming
the in train
3a
: extremely fashionable
the in thing to do
b
: keenly aware of and responsive to what is new and fashionable
the in crowd
in
nounDefinition of in (Entry 4 of 11)
Definition of in (Entry 5 of 11)
1
inch
2
inlet
In
symbolDefinition of In (Entry 6 of 11)
indium
Definition of IN (Entry 7 of 11)
Indiana
in-
prefix (1)
variants:
or il-
or im-
or ir-
Definition of in- (Entry 8 of 11)
in-
prefix (2)
variants:
or il-
or im-
or ir-
Definition of in- (Entry 9 of 11)
1
: in : within : into : toward : on
—usually il- before l illuviation , im- before b, m, or p immingle , ir- before r irradiance , and in- before other sounds infiltrate
2
: en- entry 1
imbrute imperil inspirit
-in
noun suffixDefinition of -in (Entry 10 of 11)
1a
: neutral chemical compound
insulin
b
: enzyme
pancreatin
c
: antibiotic
penicillin
2
: -ine entry 2 sense 1a
epinephrin
3
: pharmaceutical product
niacin
Definition of -in (Entry 11 of 11)
: organized public protest by means of or in favor of : demonstration
teach-in love-in
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Merriam-Webster unabridged
Share in
Time Traveler for in
The first known use of in was before the 12th century
See more words from the same century