A device or structure, such as a drawbridge, counterbalanced so that when one end is lowered the other is raised.
[French, seesaw : bas, low (from Old French, from Medieval Latin bassus) + cul, bottom (from Old French, from Latin cūlus, rump; see (s)keu- in the Appendix of Indo-European roots).]
(click for a larger image)bascule
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.