any of various primates with short tails or no tail at all
"Humans and chimpanzees are apes, which distinguishes them from monkeys that typically have long tails."
person who resembles a nonhuman primate
"The mischievous child was accused of aping his older brother's every gesture."
A primate of the clade Hominoidea, generally larger than monkeys and distinguished from them by having no tail.
"The silverback gorilla is a large ape that walks on all fours but has no tail like many other primates."
In plain English: An ape is any large, intelligent primate that lacks a tail and lives mostly in trees.
"The zoo keepers built an enclosure large enough for the chimpanzee to climb the trees."
Usage: Avoid using this term to refer to a monkey; apes are specifically distinguished from monkeys by their lack of tails. In casual conversation, do not confuse it with the verb meaning to mimic someone's behavior.
To behave like an ape.
"The children began to clap their hands and swing their arms as if they were apes after seeing the circus act."
Wild; crazy.
"His behavior was completely ape-like during the chaotic party."
The word ape entered Middle and Old English from Germanic roots meaning monkey. Its ultimate origin may be an ancient term for water that once suggested apes were seen as water sprites before taking on its current animal name.