1. A foam formed by soap or detergent agitated in water, as in washing or shaving.
2. Froth formed by profuse sweating, as on a horse.
3. Informal A condition of anxious or heated discomposure; agitation: The students were in a lather over the proposed restrictions.
v. lath·ered, lath·er·ing, lath·ers
1. To spread with or as if with lather.
2. Informal To give a beating to; whip.
1. To produce lather; foam.
2. To become coated with lather.
[Probably from Middle English latheren, to wash or soak clothes, from Old English lēthran, to cover with lather; see leu(ə)- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.