Definition of flea in English:



  • A small wingless jumping insect which feeds on the blood of mammals and birds. It sometimes transmits diseases through its bite, including plague and myxomatosis.

    Order Siphonaptera: several families and many species, including the human flea (Pulex irritans)

    • ‘Many things can lead to these hot spots including food and airborne allergens, ticks, fleas and other insect bites, and contact allergens like grass.’
    • ‘He said that fleas can jump over two hundred times their own height.’
    • ‘It put poison in his blood that killed fleas after one bite.’
    • ‘If you have been bitten by fleas, mites, or bedbugs you may have an infestation in your home, such as on one or more of your pets, and should try to find the infestation and get rid of it.’
    • ‘It is passed from bunny to bunny by biting insects such as the flea and mosquito so prevention of these is important.’
    • ‘The disease is passed onto humans through fleas which jump from the rat when it dies.’
    • ‘Lice are wingless and they cannot jump, unlike fleas, but instead they spread through physical contact.’
    • ‘Fleas spread the bacteria between cats, although there is no evidence that fleas can transmit the disease to humans.’
    • ‘We wished to avoid the constant and real threat of bedbugs, fleas, and other insect pests which we had brought home in our bags, topclothing, and soiled linens.’
    • ‘In some cases we have learned that an insect can cause harm, such as when we're bitten by a flea or mosquito.’
    • ‘Plague is transmitted by fleas that live on rodents.’
    • ‘This parcel contained the fleas that caused the plague.’
    • ‘In the end, I obeyed and fell into a comfortable sleep, ignoring the fleas that were jumping around me.’
    • ‘They're so plagued by lice, fleas, dander and mange that their coats are spotted with huge bald patches and pocked with weeping sores.’
    • ‘Imagine my horror when I had invited the parents of a Japanese student staying with me and we were all bitten by fleas!’
    • ‘In 2002, two Gardai sued the state after being bitten by fleas in Garda stations.’
    • ‘When rats die from the plague, the fleas that lived on them must seek out new sources of blood.’
    • ‘Plague mostly affected rodents, but fleas could transmit the disease to people too.’
    • ‘As he walked around the lounge his boots stuck to the floor and he became aware that he was being bitten by fleas.’
    • ‘Unlike fleas, lice can't jump from person to person.’
    insect, mite, midge
    View synonyms


  • (as) fit as a flea

    • In very good health.

      • ‘You have to be fit as a flea to take the race on, and I feel I am as fit as I could be.’
      • ‘Jack's daughter Doris Lyons said: ‘My dad was as fit as a flea.’’
      • ‘I feel as fit as a flea and my big tummy has gone down!’
      • ‘He's as fit as a flea but I think it really took a lot out of him.’
      • ‘As fit as a flea, there is no reason why he cannot make a successful transition to turf tomorrow, especially as his rating is significantly lower than the one he is now racing off on the all-weather.’
      • ‘She discovered something her legion of fans have always known: when it comes to shaking her booty, the 34-year-old is one hell of a mover and fit as a flea.’
      • ‘Some of them are as fit as a flea and going to remain as fit as a flea.’
      • ‘She never talks about it and is as fit as a flea at 85.’
      • ‘My legs were stiff, but not as stiff as on other occasions and by the afternoon I felt as fit as a flea.’
      muscular, muscly, sturdy, strapping, well built, powerfully built, strong, powerful, robust, able-bodied, vigorous, hardy, lusty, hearty, hale and hearty, brawny, burly, broad-shouldered, thickset, herculean
      View synonyms
  • a flea in one's ear

    • A sharp reproof.

      ‘she expected to be sent away with a flea in her ear’
      • ‘He spends the whole time looking at his watch, so Flynn sends him packing with a flea in his ear.’
      • ‘‘He was sent away with a flea in his ear,’ said one Labour backbencher.’
      • ‘She sent them packing with a flea in their ear of course.’
      • ‘He might give senior management a flea in their ear, but he has never claimed to be a nice guy.’
      • ‘A few weeks ago at another tournament in England, such assumptions saw one mouthy opponent dispatched with a flea in his ear.’
      • ‘‘But we soon send them away with a flea in their ear,’ explains Patrick.’
      • ‘It would have been enough to send him back with a flea in his ear.’
      • ‘I was sure the mistress was going to do the same thing as Mrs. Benson and she'd be thrown out with a flea in her ear.’
      • ‘And if anybody asks when we will be having children they will go away with a flea in their ear.’
      • ‘I mustn't have been in when he knocked on mine; he would have gone away with a flea in his ear.’


Old English flēa, flēah, of Germanic origin; related to Dutch vlo and German Floh.