A person who wakes up, without difficulty, early each morning and is alert and active during the first part of the day.
A New World nightjar of the genus Chordeiles, especially Chordeiles minor.
A nighthawker (metal detectorist who works illegally at night).
A person whose preference or custom is to remain awake and active during the night and the early morning hours.
A nightjar, especially Caprimulgus europaeus (Eurasian nightjar).