Unknown terminal 'xterm-256color'

Question

Keep getting a message in Terminal saying

tput: unknown terminal "xterm-256color"

This message typically appears when running homebrew, and while I can swear it's popped up on other places, I can't precisely remember. echo $TERM outputs xterm-256color. I'm not the best at diagnosing Terminal problems, so any help is greatly appreciated.

(I know this may be an issue when SSHing to remote servers that don't support xterm-256color, but in this case I'm just concerned about my actual system.)