blue whale

American  

[bloo hweyl, weyl] / ˈblu ˈʰweɪl, ˈweɪl /

noun

1. a migratory baleen whale, Balaenoptera musculus, mostly of oceans and seas in the Southern Hemisphere, the largest mammal ever known, growing to a length of 100 feet (30.5 meters) and having a furrowed, slate-blue skin mottled with lighter spots, in some seas acquiring a yellowish coating of diatoms on the underside: now classified as endangered, it was once hunted nearly to extinction, but international conservation efforts begun in the 1960s have enabled the blue whale population to rebound significantly.

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blue whale British  

noun

1. Also called: sulphur-bottom.  the largest mammal: a widely distributed bluish-grey whalebone whale, Sibbaldus (or Balaenoptera ) musculus , closely related and similar to the rorquals: family Balaenopteridae

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Etymology

Origin of blue whale

First recorded in 1850–55

Example Sentences

Blue whale numbers are still a tiny proportion of what they were and the species is listed as endangered by the International Union for the Conservation of Nature.

From BBC • Nov. 22, 2023

Blue whale populations plummeted by as much as 90 percent in the early to mid-20th century.

From Scientific American • Apr. 24, 2023

Blue whale 'is third seen off Sydney in 100 years'

From BBC • Dec. 23, 2021