(Britain) A metal detectorist who works illegally at night to remove artefacts from archaeological sites.

plural of nighthawker

The practice of being out late at night, for work or pleasure. / (Britain) The action of a nighthawker; the practice of metal-detecting late at night to illegally remove artifacts from restricted sites.

plural of nighthawk

(UK, regional) A nightjar, especially Caprimulgus europaeus (Eurasian nightjar). / (US) A New World nightjar of the genus Chordeiles, especially Chordeiles minor.