These words are imitative of the shrill cries made by certain birds, insects or animals. All may be used as either nouns or verbs, and most apply to human sounds as well, and have other, extended applications. A squeal is a shrill, high-pitched, somewhat prolonged nasal cry, the sort of sound that is made by a young pig. Squeak denotes a shorter, weaker cry ?a very high-pitched, thin, sharp, penetrating sound, such as the little piping noise made by a mouse. One may squeal out of surprise, excitement, fright, pain, anger or protest: children squealing with delight; to squeal in terror at a horror film. One may squeak because of a high-pitched voice or laryngitis: The boy’s voice was changing and would go from a deep tone to a shrill squeak without warning.

Screech and squawk refer to shrill, harsh cries or to sounds that are strident or raucous. A screech is a long, harsh, piercing sound ?a grating scream or shriek: a small owl that screeches weirdly. One may screech out of pain, terror or anguish: a screeching woman trapped in a burning building. Screech is also disdainfully applied to a loud, high singing voice that sounds terribly forced and strained: That soprano isn’t singing ?she’s screeching ! A squawk is a shrill, harsh cry such as is made by a parrot or a frightened hen. Squawk is applied also to any sound reminiscent of such a cry: a squawking radio.

Chirp , cheep and peep denote the high, thin, pointed sounds made by young birds. A chirp is a clear, bright sound ?a short, sharp, high-pitched cry, such as one made repeatedly by a bird or insect: chirping sparrows; the cricket’s chirp . A person may make a somewhat similar sound (or chirrup) by drawing the breath through the closed lips or tongue and teeth, as in greeting an infant or urging on a horse. A cheep is a faint, shrill sound ?a weak, feeble chirp or squeak : the cheep of a chicken. A peep is the kind of tiny cry made by young or very small creatures: the peep of a frightened mouse. Applied to human utterance, chirp means to talk or say in a quick, vivacious way, to cry out cheerfully with birdlike enthusiasm: "Good morning," chirped the children.

Applied to things, squeak designates a shrill, creaking sound indicative of stiffness or friction: the squeak of new shoes; a speaking hinge. Squeal refers to a loud, drawn-out, nasal sound that is reminiscent of a hurt, protesting cry: squealing brakes. Screech implies a harsher, more earsplitting noise: The underground train screeched to a stop.

In idiomatic speech, to squeak by or squeak through is to make it by a hair’s-breadth, to succeed by an extremely narrow margin: He just managed to squeak through , but he passed the course. In slang usage, to squeal is to turn informer, betraying one'?confederates, as in crime: You’d better not squeal if you know what’s good for you. To squawk is to complain or protest loudly in a harsh, shrill way: He really squawked when he found the hotel didn’t have his reservation. A peep is the slightest sound that one can make, especially a sign of dissatisfaction: I don’t want to hear a peep out of you.

There are also many words relating to the cries of specific animals or birds which cannot be given in full here. Thus we have the caw of a crow, coo of a dove and hoot of an owl. These are usually restricted far more than the above terms, although hoot is part of the idiom "does not give a hoot ," which means does not care at all.