Capitalizing Kinship Names and the Like

Spotlight on CMOS 8.36

A kinship name is a name for a family member, whether close or distant. Such names include mom, dad, sister, brother, aunt, uncle, cousin, and so on.

Similar words are used for people who aren’t necessarily relatives. These include words for jobs like doctor or waiter, words like sir or ma’am that are typically addressed to strangers, and terms of endearment like honey or darling.

Whether to capitalize one of these words depends at least partly on the answer to two questions: (a) Does the word refer to a family member? (b) Is the word being used in place of a name or as part of a name? If the answer to both a and b is yes, then it’s most often capitalized. Otherwise, it depends on some additional factors.

Kinship Names as Names

If you use a word like mom in place of a name, then it’s usually capitalized. To figure out whether this is true, look for an article (a, an, or the) or other determiner (such as a possessive pronoun) in front of the word. If there isn’t one, it’s probably being used as a name and should therefore be capitalized.

Should we tell Mom what we did?

What do you mean, Grandpa?


Should we tell my mom what we did?

We didn’t think of him as a grandfather.

Though words for parents and grandparents are more likely to be used in place of a name than other words of kinship, the same rule can be applied to other relatives referred to in this way.

Hey, Sis, what’s the rush?


I told my sister not to worry.

Many writers, however, will prefer lowercase for all but parents and grandparents—Hi, son! or Yes, cousin. Editors can help by fixing or querying any apparent inconsistencies.

Kinship Names with Names

If it’s a word of kinship used with a name—like Aunt or Uncle—capitalization is the norm.

Where’s Aunt Maud?


Where’s my aunt?


Where’s my aunt Maud?

As for that last example, “my aunt Maud” is strictly correct (it means “my aunt who is named Maud”). But “my Aunt Maud” could also work—for example, in a story that includes a character known mainly as Aunt Maud. And don’t forget about cousins, who can also be referred to in this way: Where’s Cousin Bob? (but My cousin Bob).

If it’s not family, the rules are a bit different.

Jobs, Titles, and Terms of Endearment

For words outside of kinship, the bar for capitalization is significantly higher than for kinship names. If it’s a job title that could be used with a name, capitalization is usually appropriate unless the word is used with an article or other determiner. But if it’s a word for a job or other word that isn’t normally used as a title, lowercase is the rule, even if the word is used in place of a name.

What would Coach do?

How much will this cost, Doctor?


Hey, waiter, could I please have some more water?

Yes, sir.


Talk to your coach.

You might refer to a Coach Lee or a Doctor Smith, but waiter and sir are not normally used as titles in that way.*

Finally, a term of endearment isn’t normally capitalized, whether used in place of a name or not.

Thanks, sweetie!

* * *

To sum things up, a kinship name used in place of a name or as part of a name is usually capitalized (What would Mom do? Thanks, Aunt Maud); otherwise, it’s lowercased (That’s my dad). For similar words referring to people, capitalize only if the word might also be used as a title (Thanks, Doc!). And be prepared to allow for exceptions.

* Not unless you’re talking about someone like Paul McCartney, who was knighted by Elizabeth II and might therefore be referred to as Sir Paul (see CMOS 8.32).

Family art by scusi / Adobe Stock.

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