Pronunciation: (nīt'lē),[key] —adj. 1. coming or occurring each night: his nightly walk to the newsstand. 2. coming, occurring, appearing, or active at night: nightly revels. 3. of, pertaining to, or characteristic of night: the nightly gloom before a storm.
—adv. 1. on every night: performances given nightly. 2. at or by night: an animal that is seen nightly.