their

[ thair; unstressed ther ]

pronoun

1. a form of the possessive case of plural they used as an attributive adjective, before a noun:

   their home;

   their rights as citizens;

   their departure for Rome.

2. a form of the possessive case of singular they used as an attributive adjective, before a noun:
   1. (used to refer to a generic or unspecified person previously mentioned, about to be mentioned, or present in the immediate context): A parent should read to their child.

      Someone left their book on the table.

      A parent should read to their child.

   2. (used to refer to a specific or known person previously mentioned, about to be mentioned, or present in the immediate context):

      I’m glad my teacher last year had high expectations for their students.

   3. (used to refer to a nonbinary or gender-nonconforming person previously mentioned, about to be mentioned, or present in the immediate context):

      My cousin Sam is bad at math, but their other grades are good.

their

/ ðɛə /

determiner

1. of, belonging to, or associated in some way with them

   their own clothes

   she tried to combat their mocking her

   their finest hour

2. belonging to or associated in some way with people in general not including the speaker or people addressed

   in many countries they wash their clothes in the river

3. belonging to or associated in some way with an indefinite antecedent such as one, whoever, or anybody

   everyone should bring their own lunch

Usage

See they

Grammar Note

See he ¹, me, they.

Word History and Origins

Origin of their¹

First recorded in 1150–1200; Middle English their(e), ther(e), from Old Norse theirra “their”; replacing Old English thāra, thǣra; they

Word History and Origins

Origin of their¹

C12: from Old Norse theira (genitive plural); see they , them

Example Sentences

Researchers measured each baby's weight, length and body fat at birth and then several times over the first 12 months of their lives.

From Science Daily

Babies born to mothers with GDM had higher levels of body fat at birth, but these infants showed slower fat gain during their first year of life, suggesting a flexibility in early-life growth patterns that earlier studies may have missed.

From Science Daily

The study, out today in the American Journal of Clinical Nutrition, challenges current views on obesity risk by showing slower fat gain among these infants compared to others in their first year.

From Science Daily

Leveraging a unique statistical analysis and applying it to ancient DNA extracted from human skeletal remains, a team of researchers from The University of Texas at Austin and the University of California, Los Angeles has revealed new insights into how ancient Europeans adapted to their environments over 7,000 years of European history.

From Science Daily

Current anti-inflammatory treatments bring relief but often fall short, as patients can lose their response to these medications over time, suffer relapses, and experience significant side effects.

From Science Daily

Their Vs. There Vs. They're

What’s the difference between their, there, and they're?

Their is the possessive form of the personal pronoun they, essentially meaning belonging to or possessed by them, as in Is that their car, or ours? There is commonly used to introduce sentences or to indicate where something is, as in It’s over there, next to the window. They’re is a contraction of they are.

There are many instances in which they’re confused because their pronunciations are exactly the same. (See what we did there?)

There are easy ways to remember which spelling is right, and they’re actually built into each word.

You can remember that their is the one that’s used to show possession (like his and her) by remembering that it includes the word heir (a person who inherits possessions).

When it’s used to indicate location, there functions a lot like here (even though it can mean the opposite), and the word here is right inside of it.

The apostrophe in they’re indicates that it’s a combination of two words and signals that it’s the one you want to use when you mean they are.

Here’s an example of their, there, and they’re used correctly in the same sentence.

Example: It’s hard to work as a team in that environment—when they’re in there, they’re their own worst enemies.

Want to learn more? Read the full breakdown of the difference between their, there, and they’re.

Quiz yourself on their vs. there vs. they're!

In what order should their, there, and they’re be used in the following sentence?

_____ shoes are over _____, right next to where _____ sitting.

A. their, there, they’re
B. there, they’re, their
C. they’re, their, there
D. their, they’re, there