n.
An ion or group of ions having a positive charge and characteristically moving toward the negative electrode in electrolysis.
[Greek kation, something going down, from neuter present participle of katienai, to go down : kat-, kata-, cata- + ienai, to go.]
cationic cat'i·on'ic (kăt'ī-ŏn'ĭk) adj.
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.