gecko

n. any of a number of small nocturnal lizards who eat insects and make shrill or clicking noises

Geckos are small to average sized lizards belonging to the family Gekkonidae which are found in warm climates throughout the world. Geckos are unique among lizards in their vocalizations, making chirping sounds in social interactions with other geckos. There are 1,196 different species of geckos. [1] The name stems from the Malay word gekoq, imitative of its cry. Geckos are unusual in other respects as well. Most geckos have no eyelids and instead have a transparent membrane which they lick to clean. Many species will, in defense, expel a foul-smelling material and feces onto their aggressors. Many species have specialized toe pads that enable them to climb smooth vertical surfaces and even cross indoor ceilings with ease. These antics are well-known to people who live in warm regions of the world where several species of geckos make their home inside human habitations. These species (for example the house gecko) become part of the indoor menagerie and are seldom really discouraged because they feed on insect pests.
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Noun
1. any of various small chiefly tropical and usually nocturnal insectivorous terrestrial lizards typically with immovable eyelids; completely harmless
(hypernym) lizard
(hyponym) flying gecko, fringed gecko, Ptychozoon homalocephalum

n. gecko, any of a number of small nocturnal lizards who eat insects and make shrill or clicking noises

(n.)
Any lizard of the family Geckonidae. The geckoes are small, carnivorous, mostly nocturnal animals with large eyes and vertical, elliptical pupils. Their toes are generally expanded, and furnished with adhesive disks, by which they can run over walls and ceilings. They are numerous in warm countries, and a few species are found in Europe and the United States. See Wall gecko, Fanfoot.