A black light.

(idiomatic, archaic) To bear marks of great study and labor.

(Arab folklore, Arabic fiction and derived works) An oil lamp that can be rubbed in order to summon a genie who grants wishes.

A mechanical lamp for lighthouses, in which a superabundance of oil is pumped to the wick tube by clockwork.

(now rare or historical) Either of the lamps on either side of a gig carriage; a headlamp. / (in the plural, dated, slang) Spectacles.

(now historical) A type of oil lamp with a circular hollow wick and glass chimney which allow a current of air both inside and outside of the flame.

Fresnel lantern

A lamp whose light exits through a narrow slit

(philosophy) A hypothetical lamp in a philosophical paradox. The lamp is repeatedly turned on and off by means of a switch; at the end of this time period, regarded as the sum of an infinite series of intervals, it seems paradoxically that the lamp cannot be either on or off.

(countable) Streetlight.