Definition of platy in English:



  • A small live-bearing freshwater fish of Central America, which is popular in aquaria.

    • ‘Examples include the jewelfish and spotted tilapia; and livebearers, such as swordtails, platies and mollies, and armored catfishes.’
    • ‘In the swordless platies, females also prefer males with artificially attached swords over conspecific males.’
    • ‘Coexistence of the two types of sex-determining mechanisms in the same species is unusual and has been reported only in the platy fish, housefly, and midge.’
    • ‘Prompted by my concern for Linda's ‘tough-love’ hardened goldfish and platies, I was given Nigel as an outlet for my protective zeal.’
    • ‘He's lived happily for the past four months with a platy and two neon tetras in a five gallon aquarium.’


Early 20th century: colloquial abbreviation of modern Latin Platypoecilus (former genus name), from Greek platus broad + poikilos variegated.