Definition of "cation" [cat•i•on]

• An ion or group of ions having a positive charge and characteristically moving toward the negative electrode in electrolysis. (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.

• "The recession has been among us for long enough now that the "stay-cation" is no longer a novel concept."
• "As a result, the iron cation is released, but the apo-transferrin, which has high affinity for the receptor at acidic pH, remains bound strongly."
• "In the words of soil science, this functioning like a storage battery for minerals is called cation exchange capacity."