in

1 of 11

preposition

ˈin How to pronounce in (audio)
ən,
ᵊn
1
a
used as a function word to indicate inclusion, location, or position within limits
in the lake
wounded in the leg
in the summer
b
: into sense 1
went in the house
2
used as a function word to indicate means, medium, or instrumentality
written in pencil
bound in leather
3
a
used as a function word to indicate limitation, qualification, or circumstance
alike in some respects
left 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

2 of 11

adverb

1
a(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
2
a
: 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

3 of 11

adjective

1
a
: that is located inside or within
the in part
b
: that is in position, operation, or power
the in party
2
: that is directed or bound inward : incoming
the in train
3
a
: extremely fashionable
the in thing to do
b
: keenly aware of and responsive to what is new and fashionable
the in crowd

in

4 of 11

noun

1
: one who is in office or power or on the inside
a matter of ins versus outs
2
: influence, pull
enjoyed some sort of in with the commandantHenriette Roosenburg

in

5 of 11

abbreviation (1)

1
inch
2
inlet

In

6 of 11

symbol

indium

IN

7 of 11

abbreviation (2)

Indiana

in-

8 of 11

prefix (1)

variants or il- or im- or ir-
: not : non-, un-
usually il- before l
illogical
, im- before b, m, or p
imbalance
immoral
impractical
, ir- before r
irreducible
, and in- before other sounds
inconclusive

in-

9 of 11

prefix (2)

variants or il- or im- or ir-
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

10 of 11

noun suffix

1
a
: neutral chemical compound
insulin
b
: enzyme
pancreatin
c
: antibiotic
penicillin
2
: -ine entry 2 sense 1a
epinephrin
3
: pharmaceutical product
niacin

-in

11 of 11

noun combining form

: organized public protest by means of or in favor of : demonstration
teach-in
love-in
Phrases
in for
: certain to experience
in for a rude awakening

Examples of in in a Sentence

Preposition Don't come in here with those muddy feet! drawn on the wall in crayon Adverb She went in and closed the door. I lost my keys and now I can't get in. The burglars broke in through the kitchen window. The pool is deep. Be careful not to fall in. The boss called us in for a conference. The fog was closing in fast. Get your orders in early! Is the train in yet? Adjective the in thing to do the in place to go It's what the in crowd is wearing this season. Noun When you're trying to get started in show business, it helps to have an in. They must have an in with the boss.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Preposition
Frankly Ohio State should not be in after today’s debacle. Kennington Smith Iii, The Athletic, 1 Dec. 2024 Stay warm in the Vintage Rib Cardigan, now $37 (originally $69). Kelsey Glennon, Travel + Leisure, 1 Dec. 2024
Adverb
Fold in potatoes, cheese, and onion: Add and fold in thawed hashbrown potatoes, Cheddar, and onion. Darcy Lenz, Southern Living, 1 Dec. 2024 Technology tests in include regolith sampling, regolith adherence, Global Navigation Satellite System abilities, radiation tolerant computing, and dust mitigation using electrodynamic fields. Richard Tribou, Orlando Sentinel, 30 Nov. 2024
Adjective
Optical atomic clocks, accurate to picoseconds, will enable satellite constellations and ground stations to determine satellites’ locations with centimeter-level precision—avoiding potentially catastrophic in-orbit collisions. Paul Lipman, Forbes, 8 Oct. 2024 Southland Prep celebrates at ‘All-In’ college rally Southland College Prep Charter High School in Richton Park recently celebrated for the tenth consecutive year that all members of its senior class have been accepted to college. Paul Eisenberg, Chicago Tribune, 5 May 2023
Noun
This was perhaps understandable in the immediate days after the vote, as Casey entertained the forlorn hope that outstanding mail-in and absentee ballots in populous Democratic-leaning counties would disproportionately break in his favor. The Editors, National Review, 20 Nov. 2024 In 2020, this was further compounded by a surge in mail-in and absentee ballots amid the COVID-19 pandemic, which required more time for verification and processing, delaying the final vote count by several days. Brandi D. Addison, Austin American-Statesman, 5 Nov. 2024 See all Example Sentences for in 

Word History

Etymology

Preposition

Middle English, from Old English; akin to Old High German in in, Latin in, Greek en

Prefix (1)

Middle English, from Anglo-French, from Latin; akin to Old English un-

Prefix (2)

Middle English, from Anglo-French, from Latin, from in in, into

Noun suffix

French -ine, from Latin -īna, feminine of -īnus of or belonging to — more at -en

Noun combining form

sit-in

First Known Use

Preposition

before the 12th century, in the meaning defined at sense 1a

Adverb

before the 12th century, in the meaning defined at sense 1a(1)

Adjective

15th century, in the meaning defined at sense 1a

Noun

1741, in the meaning defined at sense 1

Time Traveler
The first known use of in was before the 12th century

Dictionary Entries Near in

Cite this Entry

“In.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/in. Accessed 9 Dec. 2024.

Kids Definition

in

1 of 6 preposition
(ˈ)in How to pronounce in (audio)
ən,
ᵊn
1
a
used to show enclosing, including, or placing within limits
in the lake
wounded in the leg
in the summer
in a minute
b
: into sense 1a
went in the house
don't come in here with those muddy feet
2
used to show means or medium
written in pencil
works in plastics
photographs in color
3
a
used to show a state or condition
we're in trouble
is made in three sizes
in power
in love
b
: into sense 2a
broke in pieces
4
used to show manner or purpose
said in reply
5
used to show the larger member of a ratio
one in five

in

2 of 6 adverb
1
a
: to or toward the inside
went in and closed the door
b
: to or toward a place
flew in yesterday
c
: so as to be or seem near
play close in
d
: into the midst of something
mix in the flour
e
: to or at its proper place
fit a piece in
f
: so as to be in agreement
fell in with our plans
2
a
: on the inner side : within
everyone is in
b
: on good terms
in with the right people
c
: in fashion
boots are in this year
d
: at hand : on hand
the evidence was in
harvests are in

in

3 of 6 adjective
1
a
: being inside or within
the in part
b
: being in power
the in party
2
: directed or bound inward : incoming
the in train
3
a
: very fashionable
the in thing to do
the in place to go
b
: very aware of and taking part in what is new and fashionable
the in crowd

in-

4 of 6 prefix
variants or il- or im- or ir-
: not : non-, un-
usually il- before l
illogical
, im- before b, m, or p
imbalance
immoral
impractical
, ir- before r
irreducible
, and in- before other sounds
inconclusive

in-

5 of 6 prefix
variants or il- or im- or ir-
1
: in : within : into : toward : on
usually il- before l, im- before b, m, or p, ir- before r, and in- before other sounds
infiltrate
2
: en- sense 2
imperil

-in

6 of 6 noun suffix
ən
: chemical compound
stearin
insulin
niacin
Etymology

Prefix

derived from Latin in- "not"

Prefix

derived from Latin in "in, into"

Noun suffix

derived from Latin -ina, -inus (adjective suffixes)

Medical Definition

in

1 of 2 abbreviation
inch

In

2 of 2 symbol
indium

Legal Definition

in

preposition
: under the law of : based on
brought an action in negligenceNational Law Journal

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