Source : WordNet®

apropos
     adj : of an appropriate or pertinent nature [ant: {malapropos}]
     adv 1: by the way; "apropos, can you lend me some money for the
            weekend?" [syn: {incidentally}]
     2: at an opportune time; "your letter arrived apropos" [syn: {seasonably},
         {timely}, {well-timed}]