oc‧ca‧sion‧al‧ly S2 W3 / əkeɪʒ ə nəli / 副词

sometimes, but not regularly and not often :

Occasionally Alice would look up from her books.

We only see each other very occasionally (= rarely ) .

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In everyday English, people often say once in a while rather than occasionally :

We still see her once in a while .

THESAURUS

sometimes on some occasions but not always : Sometimes, I wish I was still living in Tokyo. | He sometimes plays football with my brother.

occasionally ( also on occasion written ) used about something that only happens a few times. Occasionally is used when something happens more rarely than sometimes : I prefer trousers but I do wear skirts occasionally. | Occasionally, operations have to be cancelled. | On occasion, prisoners were allowed visits from their families.

(every) now and then/again ( also from time to time ) sometimes but not often or regularly : We still call each other every now and then. | Every now and again, an invention comes along which changes people’s lives completely. | Even experienced doctors make mistakes from time to time.

every so often sometimes at fairly regular periods : He looked up from his book every so often. | Every so often, a train whizzed past.

at times if something happens at times, it happens sometimes but is not what usually happens : The job can be frustrating at times. | At times I’ve wondered whether I made the right decision in moving here.

(every) once in a while sometimes but very rarely : We only see each other every once in a while.