What does "first off" mean?

Firstly; before anything else. Often used to introduce the first in a list of points to be made in conversation.

What is a synonym for "first off"?

Common synonyms include: first, first of all, firstly, foremost.

adv

adv ·Rare ·Advanced level

Adverb

1
Firstly; before anything else. Often used to introduce the first in a list of points to be made in conversation. idiomatic, not-comparable, sequence

Adverb