aperiodic
Concise Oxford English Dictionary © 2008 Oxford University Press:
aperiodic/eɪpɪərɪˈɒdɪk/
▶adjective chiefly Physics
- 1 not periodic; irregular.
- 2 damped to prevent oscillation or vibration.
– derivatives
aperiodicity noun.
aperiodicity noun.
'aperiodic' also found in these Oxford entries:

