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swellfish

American  
[swel-fish] / ˈswɛlˌfɪʃ /

noun

PLURAL

swellfish

PLURAL

swellfishes
  1. puffer.


swellfish British  
/ ˈswɛlˌfɪʃ /

noun

  1. a popular name for puffer

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of swellfish

An Americanism dating back to 1800–10; swell + fish