Source : WordNet®

pit-a-pat
     adv 1: as of footsteps; "he came running pit-a-pat down the hall"
            [syn: {pitty-patty}, {pitty-pat}, {pitter-patter}]
     2: describing a rhythmic beating; "his heart went pit-a-pat"
        [syn: {pitty-patty}, {pitty-pat}, {pitter-patter}]