Antonyms of adv frequently

1 sense of frequently

Sense 1
frequently, often, oftentimes, oft, ofttimes -- (many times at short intervals; "we often met over a cup of coffee")
       Antonym of infrequently (Sense 1)
      => infrequently -- (not many times; "in your 1850 church you not infrequently find a dramatic contrast between the sumptuous appointments of the building itself and the inhuman barrack-like living conditions in the church room")

Synonyms of adv frequently

1 sense of frequently

Sense 1
frequently, often, oftentimes, oft, ofttimes -- (many times at short intervals; "we often met over a cup of coffee")