i Register
In some senses, nighthawk is marked as UK, US, historical. Watch for register when choosing this word.
noun
A nightjar, especially Caprimulgus europaeus (Eurasian nightjar).
A New World nightjar of the genus Chordeiles, especially Chordeiles minor.
The swallows circled around and I watched them and the night-hawks flying above the roofs and drank the Cinzano.
A person whose preference or custom is to remain awake and active during the night and the early morning hours.
A nighthawker (metal detectorist who works illegally at night).
An unlicensed prostitute who worked the roadsides at night.