ape
A large, smart primate without a tail, like a chimpanzee.
An ape is a type of intelligent primate that includes gorillas, chimpanzees, orangutans, bonobos, and gibbons. Unlike monkeys, apes have no tails, larger brains relative to their body size, and more flexible shoulders that let them swing through trees. Humans are actually classified as great apes too, though we usually use the word to refer to our non-human cousins.
Apes are remarkable creatures. Chimpanzees use tools, solve complex problems, and live in sophisticated social groups. Gorillas are gentle giants despite their massive size and strength. Orangutans build sleeping nests in trees every night and can recognize themselves in mirrors, a sign of self-awareness that few animals possess.
As a verb, ape means to imitate or copy someone, usually in an exaggerated or mocking way. If your friend apes your teacher's voice and gestures, they're mimicking how the teacher talks and moves.
You might hear someone say another person “went ape,” meaning they became extremely excited, angry, or wild. This is slang and doesn't reflect how actual apes normally behave.