their vs Thi, What's the Difference?

Which to use

“their” is a determiner and “Thi” is a name - they look or sound alike but fill different roles in a sentence.

#56
“their” frequency rank: #23,700
“Thi” frequency rank: 23756
confusion score

Side-by-Side Comparison

Feature	their	Thi
Definition	Belonging to, from, of, or relating to, them (plural).	A surname from Vietnamese.

Where the spellings diverge

Shared letters are muted; the letters that actually set their and Thi apart are highlighted. They share 3 letters in sequence, which is exactly why the eye skips the difference.

5 ch

their

3 ch

Thi

Spelling & Dictionary Insight

Our dataset has no pronunciation recorded for both members, so the reliable separator here is grammatical: their is adeterminer and Thianame. On the page they differ by 2 letter(s) in length. Our composite confusion score for this pair is 23756, derived from the frequency rank of both members and their visual similarity.

their is recorded at frequency rank #56, classified as adet, pronounced /ðɛə/. Thi is at rank #23,700, tagged as aname.

Glosses for this pair are partially populated in our dataset, but the full side-by-side definitions above should still guide you to the right choice.

With a confusion score of 23756, this pair ranks #406,996 of 530,003 scored English confusable pairs - a relatively easy-to-tell-apart pair.

Orthographic DNA of their vs Thi

Shared letters: hit. Private to "their": er. Private to "Thi": -.

"their" · 5 letters · shape CCVVC · "Thi" · 3 letters · shape CCV

Known mistypes of this pair

their ← hteir · tehir · theirr · theri · thheir · ttheir

Frequency comparison

their#56

Thi#23,700

Source: FrequencyWords open word-frequency list

Frequently Asked Questions

Can "their" and "Thi" be used interchangeably?

No - they are not even the same part of speech. "their" is a determiner and "Thi" a name, so a sentence built for one is usually ungrammatical with the other.

Which is more common, "their" or "Thi"?

"their" is the more common of the two: it sits at frequency rank #56 in our English list, against #23,700 for "Thi". That is a wide gap, so in ordinary text the rarer spelling is the one worth double-checking.

Remembering their vs Thi

The fastest way to pick the right one every time.

Check the role first: if you need a determiner, it's “their”; for a name, it's “Thi”.
See each word in full, definition, IPA, etymology and its other confusables. Full “their” entry
Browse more pairs most likely to be confused. Most confusable