a. Conforming to dietary laws; ritually pure: kosher meat.
b. Observing dietary laws: a kosher household.
c. Selling or serving food prepared in accordance with dietary laws: a kosher restaurant.
2. Informal Legitimate; permissible: Is it kosher to wear jeans in the office?
tr.v. ko·shered, ko·sher·ing, ko·shersIdiom:
To make proper or ritually pure.
To observe Jewish dietary laws.
[Yiddish kosher, from Ashkenazi Hebrew kóšer, from Hebrew kāšēr, fitting, proper, from kāšēr, to be fitting, to succeed; see kṯr in the Appendix of Semitic roots.]
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.