tr. & intr.v., -ened, -en·ing, -ens.
To make or become tight or tighter.
tightener tight'en·er n.
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
