To grind and knead (rubber, for example) into a pulp.(verb-transitive)
To chew food.(verb-intransitive)
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.
Use "masticate" in a sentence
"I did, however, get to masticate sika deer, which is sensational."
"It is also possible that carbohydrates are easier to masticate compared to some other foods such as meat which may be easier to eat when puréed and spoon-fed."
"After which I need to go away and mentally masticate."