Definition of platy in English:

platy

(also platyfish)

Pronunciation /ˈpladēˌfiSH/ /ˈplædiˌfɪʃ/

nounplaty, platyfishes

  • A small livebearing freshwater fish of Mexico and Central America, popular in aquariums.

    Genus Xiphophorus, family Poeciliidae: several species, in particular X. maculatus, which has been bred in a wide variety of colors

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

Origin

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