irregular

CEFR: C1-C2 /ir-reg-u-lar/ [ih2.r.eh1.g.y.ah0.l.er0]

Definition: Occurring at uneven or varying rates or intervals

Example Sentences:

Income can be withdrawn at irregular intervals to suit individual circumstances as long as the payments are in accordance with the above limits.

The rhythm is irregular, and the rate can vary or become sinus bradycardia because of the long pauses.