The name Islas Canarias is likely derived from the Latin name Canariae Insulae, meaning "Islands of the Dogs", a name applied originally only to Gran Canaria. According to the historian Pliny the Elder, the Mauretanian king Juba II named the island Canaria because it contained "vast multitudes of dogs of very large size".

Another speculation is that the so-called dogs were actually a species of monk seal (canis marinus or "sea dog" was a Latin term for "seal"), critically endangered and no longer present in the Canary Islands. The dense population of seals may have been the characteristic that most struck the few ancient Romans who established contact with these islands by sea.

Alternatively, it is said that the original inhabitants of the island, Guanches, used to worship dogs, mummified them and treated dogs generally as holy animals. The ancient Greeks also knew about a people, living far to the west, who are the "dog-headed ones", who worshiped dogs on an island. Some hypothesize that the Canary Islands dog-worship and the ancient Egyptian cult of the dog-headed god, Anubis are closely connected but there is no explanation given as to which one was first.

The connection to dogs is retained in their depiction on the islands' coat-of-arms

What is certain is that the name of the islands does not derive from the canary bird; rather, the birds are named after the islands.

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