anal fin

noun

in fishes

: a median unpaired fin on the lower posterior part of the body behind the vent and sometimes confluent with the caudal fin see fish illustration

Word History

First Known Use

1769, in the meaning defined above

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Rhymes for anal fin

• aneurin
• crystallin
• eosin
• mandolin
• porphyrin
• underpin
• violin
• akin
• auxin
• buckskin
• chagrin
• deerskin

Kids Definition

anal fin

noun

: a single fin located on the lower back part of the body of a fish behind the excretory opening