Informal Something, especially a game fish, that is large for its kind.(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.
Use "lunker" in a sentence
""We have to be able to determine if a fish that comes out of a lake as a lunker is a fish that we put in there," he said."
"This water I covered faithfully with as little success as before, and when I had finished, crawled out upon the apron of the dam, and saw, directly underneath, eighteen or twenty trout, ranging from six inches in length to one old "lunker" over twenty."
"Each person added another $1 each for a prize for the "lunker," or heaviest fish."