I infrequently check my old emails, but when I do I often find important messages.

The scientist cataloged the infrequencies in the dataset to better understand unusual patterns.

The infrequency of safety inspections raised concerns about long-term equipment reliability.

Her infrequent visits to the old bookstore made each meeting feel like a special event.

The historian noted several infrequences in the ancient records that suggested previously unknown rituals.

The infrequence of his visits made each one feel like a small celebration.