Meaning

noun any of various small chiefly tropical and usually nocturnal insectivorous terrestrial lizards typically with immovable eyelids; completely harmless

originThe modern form was probably borrowed into English and other European languages from Dutch gekko (1718). Contemporary English forms were chacco (1711) and jackoa (1724). The further origin is not quite clear. Some sources mention a supposed Malay gekok, gekoq, or gekop, which would be imitative of the gecko’s chirping sound. Another theory derives it from Acehnese gèh-gòh (“busy”).

Etymology from Wiktionary, CC BY-SA 3.0