apropos, adv.
introducing a different topic
<adv.all> freq. cnt.: 7 freq. cnt.: 5 freq. cnt.: 2
apropos by the bye by the way incidentally
sample sentences
"incidentally, I won't go to the party"
at an opportune time
<adv.all> freq. cnt.: 1 freq. cnt.: 1
apropos seasonably timely well-timed