Definition of St Peter's fish in English:

St Peter's fish

noun

  • A fish with a dark mark near each pectoral fin, in particular a widely farmed cichlid of Africa and the Middle East (also called tilapia).

    • ‘In Galilee St Peter's fish, Sarotherodon galilaeus (Cichlidae), male care, female care and biparental care all occur in the same population.’
    • ‘In the Pacific regions or in small lakes in the United States, St. Peter's Fish are known by the name Tilapia or, more often than not, Sunfish.’

Origin

With biblical allusion to Matt. 17:27.