From Longman Dictionary of Contemporary Englishshoalshoal /ʃəʊl $ ʃoʊl/ noun [countable] 1 HBPGROUP OF PEOPLEa large group of fish swimming together SYN schoolshoal of a shoal of fish► see thesaurus at group2 HEOa small hill of sand just below the surface of water that makes it dangerous for boats
Examples from the Corpus
shoal• Above: A shoal for £2?• Keep Pim. pictus in a shoal.• If you find yourself close to a shoal of feeding chub, take advantage and watch.• Peaceful and lively, the fish is best in small shoals because loners or pairs become nervous.• Green Chromis are ideal in small shoals.• But pirates lurked in the shoals of global commerce, ready to plunder the cargoes.• Swells passed through them, shoals surfaced without warning.• They hugged the shore, Clayt pulling hard on the wheel at unseen shoals, flying over low water.Origin shoal 1. Old English scolu “large group”2. (1300-1400) shoal “not deep” ((11-20 centuries)), from Old English sceald 