Rare, infrequent, occasional, seldom. (All carry a connotation of short duration as well.)
It occurs preceding nominalized verbs.
Sasa'at pala'ine si luma'in.
He is seldom at the house (lit. his being at the house is infrequent).
Sasa'at sa' pagtāringne sangemin.
His crying at night is rare.