Search Result for "aperiodic": 
Wordnet 3.0

ADJECTIVE (1)

1. not recurring at regular intervals;
[syn: aperiodic, nonperiodic]



WordNet (r) 3.0 (2006):

aperiodic
    adj 1: not recurring at regular intervals [syn: aperiodic,
           nonperiodic] [ant: periodic, periodical]