n (context|ichthyology) One of the posterior paired fins of fishes; pelvic fin; ventral fin.(reference-book | last =| first = | authorlink = | coauthors = | editor =Gove, Philip Babcock | others = | title = Webster's Third International Dictionary of the English Language Unabridged | origdate = | origyear = 1909 | origmonth = | url = | format = | accessdate = | accessyear = | accessmonth = | edition = | date = | year =1976 | month = | publisher =G. & C. Merriam Co. | location = Springfield, MA | language = | id = | doi = | isbn =0-87779-101-5 | lccn = | ol = | pages =2 | chapter = | chapterurl = | quote =)