Also found in: Medical.
The second stage of the oral phase of psychosexual development, from approximately 8 to 18 months of age, during which a child may express hostility by biting, spitting, or chewing on objects.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.