Is my aunt's husband my blood relative?

No. He's related to you through marriage only, so you'd expect to share no DNA (unless you're related some other way).

What is my aunt's husband's brother to me?

There's no standard name. He's your uncle-by-marriage's brother and not related to you.

Your aunt's husband is your uncle by marriage. He is related to you by marriage, not by blood.

Your aunt's husband is your uncle by marriage. He is related to you by marriage, not by blood.

you them common ancestors double line: marriage

Most families just say aunt or uncle.

Your aunt's husband is your uncle by marriage. He isn't a blood relative, but in everyday English he's simply your uncle.

If he and your aunt divorce, many people keep calling him uncle. Strictly, he becomes your aunt's former husband.

How we worked it out

Follow the chain one step at a time:

…

Tap relatives in order, like mother, cousin, daughter

More: grandchildren, great-, half-, step- and in-laws

Any sex Grandchildren and great- Half Step In-laws

Or type it the way you'd say it

…is what to

I am