Definition of "swordtail" []

• A small, brightly colored, live-bearing freshwater fish (Xiphophorus helleri) of Central America, having a long tapering extension of the caudal fin in the male and popular in home aquariums. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• " One Activision Keystone Kapers cartridge for Atari 2600, borrowed by you, claimed lost, $19.99; one baseball bat shattered in anger, without apology after humiliating strikeout, $7.99; one green swordtail fish, leapt to its death after you opened aquarium lid, chased it with net, $0.79."
• "There's hope for the less-than-perfect male – if you're a swordtail fish, that is."
• "As the size and age of female swordtail fish increase, so does the preference for males with asymmetrical markings, according to a new Ohio University study."