The definition of a shoal is a large group, particularly of fish, or a sandy, shallow area of water.(noun)
Shoal is defined as to come together in a group, or to become shallow, or to sail into a shallow part of the water.(verb)
See shoal in Webster's New World College Dictionary
Origin: via dial. < OE scolu, multitude, school of fish, akin to Du school < IE *skēl- < base *(s)kel-, to cut > shield
Origin: < earlier adj. shoal, shallow < ME scholde < OE sceald, shallow; akin to OE *scealw, shallow
See shoal in American Heritage Dictionary 4
Origin: Middle English shold, shallow, shallows
Origin: , from Old English sceald, shallow.
Origin: Probably Middle Low German
Origin: or Middle Dutch schōle; see skel-1 in Indo-European roots.
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