UK:*UK and possibly other pronunciationsUK and possibly other pronunciations/ˈræt/US:USA pronunciation: IPA and respellingUSA pronuncation: IPA/ræt/ ,USA pronunciation: respelling(rat)

Inflections of 'rat' (v): (⇒ conjugate)
v 3rd person singular
v pres pverb, present participle: -ing verb used descriptively or to form progressive verb--for example, "a singing bird," "It is singing."
v pastverb, past simple: Past tense--for example, "He saw the man." "She laughed."
v past pverb, past participle: Verb form used descriptively or to form verbs--for example, "the locked door," "The door has been locked."

WordReference Random House Learner's Dictionary of American English © 2020
rat /ræt/USA pronunciation   n., interj., v.,  rat•ted, rat•ting. 
n. [countable]
  1. Mammalsa long-tailed animal, a rodent, that resembles a mouse but is larger.
  2. Slang Termsa scoundrel;
    a disloyal or untrustworthy person.
  3. Slang Termsa person who abandons or betrays associates.

  1. Slang Termsrats, (used to show disgust or disappointment).

  1. Slang Termsto inform on or betray one's associates:[+ on]She ratted on us when the cops caught her.
rat•like, adj. 

WordReference Random House Unabridged Dictionary of American English © 2020
rat  (rat),USA pronunciation n., interj., v.,  rat•ted, rat•ting. 
  1. Mammalsany of several long-tailed rodents of the family Muridae, of the genus Rattus and related genera, distinguished from the mouse by being larger.
  2. Mammalsany of various similar or related animals.
  3. Slang Termsa scoundrel.
  4. Slang Terms
    • a person who abandons or betrays his or her party or associates, esp. in a time of trouble.
    • an informer.
    • a scab laborer.
  5. Slang Termsa person who frequents a specified place:mall rat; gym rat.
  6. Clothinga pad with tapered ends formerly used in women's hair styles to give the appearance of greater thickness.
  7. smell a rat, to suspect or surmise treachery;
    have suspicion:After noting several discrepancies in his client's story, the attorney began to smell a rat.

  1. Slang Termsrats, (an exclamation of disappointment, disgust, or disbelief.)

  1. Slang Terms
    • to desert one's party or associates, esp. in a time of trouble.
    • to turn informer;
      squeal:He ratted on the gang, and the police arrested them.
    • to work as a scab.
  2. to hunt or catch rats.

  1. Clothingto dress (the hair) with or as if with a rat.
ratlike′, adj. 
  • bef. 1000; Middle English rat(t)e, Old English ræt; cognate with Dutch rat, German Ratz, Ratte

rat, +n. 
  • Slang Termsa person who frequents a specified place:a mall rat; gym rats.

  • Collins Concise English Dictionary © HarperCollins Publishers::
    rat /ræt/ n
    1. any of numerous long-tailed murine rodents, esp of the genus Rattus, that are similar to but larger than mice and are now distributed all over the world
    2. informal a person who deserts his or her friends or associates, esp in time of trouble
    3. informal a worker who works during a strike; blackleg; scab
    4. informal a despicable person
    5. smell a ratto detect something suspicious
    vb (rats, ratting, ratted)
    1. (intransitive) usually followed by on: informal to divulge secret information (about); betray the trust (of)
    2. to default (on); abandon
    3. to hunt and kill rats
    Etymology: Old English rætt; related to Old Saxon ratta, Old High German rato
    'rat' also found in these entries (note: many are not synonyms or translations):
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