What is the meaning of Apropos?

Of an appropriate or pertinent nature.

By the way, incidental.

Regarding, concerning, in regard to, on the subject of:

By the way.

Timely; at a good time.

To the purpose; appropriately.

Fittingness, pertinence.

aside

apropos (regarding or concerning)

apropos

speaking of, apropos

Source: wiktionary.org