purr

UK: /ˈpɜː^r/ US: /pɝ/ ,(pûr)

WordReference Random House Learner's Dictionary of American English © 2025

purr /pɜr/   n. 

[countable]
1. Animal Behavior the low, continuous, vibrating sound a cat makes, as when contented.
2. any similar sound:
   the purr of the car's engine.

v. 

3. Animal Behavior to utter such a sound: [no object]
   The cat purred quietly.
   [~ + object]
   The cat purred its contentment.
4. to make a similar sound:
   [no object] The new engine purred.
5. to say in a purr:
   [used with quotations] "Right this way,'' she purred.

WordReference Random House Unabridged Dictionary of American English © 2025

purr  (pûr), v.i. 

1. Animal Behavior to utter a low, continuous, murmuring sound expressive of contentment or pleasure, as a cat does.
2. (of things) to make a sound suggestive of the purring of a cat:
   The new motor of the car purred.

v.t. 

3. Animal Behavior to express by or as if by purring.

n. 

4. Animal Behavior the low, vibrating sound made by a cat by the contracting of the laryngeal muscles and the diaphragm as it breathes.
5. a sound resembling this.
6. Animal Behavior the act of purring.

Also, pur. 

• imitative 1595–1605

purr′ing•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

purr / pɜː/ verb

1. (intransitive) (esp of cats) to make a low vibrant sound, usually considered as expressing pleasure, etc
2. (transitive) to express (pleasure, etc) by this sound

noun

1. a purring sound

Etymology: 17th Century: of imitative origin; compare French ronronner to purr, German schnurren, Dutch snorren