adj. A comparative of little.
1. Not as great in amount or quantity: had less time to spend with the family.
2. Lower in importance, esteem, or rank: no less a person than the ambassador.
3. Consisting of a smaller number.
With the deduction of; minus: Five less two is three.
adv. Comparative of little.
To a smaller extent, degree, or frequency: less happy; less expensive.
1. A smaller amount: She received less than she asked for.
2. Something not as important as something else: People have been punished for less.
Not at all: He had a less than favorable view of the matter.
Certainly not: I'm not blaming anyone, much less you.
[Middle English lesse, from Old English lǣssa (adj.) and lǣs (adv.); see leis-2 in the Appendix of Indo-European roots.]
Usage Note: The traditional rule holds that fewer should be used for things that can be counted (fewer than four players), while less should be used with mass nouns for things of measurable extent (less paper; less than a gallon of paint). The Usage Panel largely supports the traditional rule. In our 2006 survey, only five percent accepted the sentence There are less crowds at the mall these days, while 28 percent accepted the following sentence, in which less is contrasted with more: The region needs more jobs, not less jobs. The Panel was a little more accepting (but still not in favor) of the familiar supermarket usage The express lane is reserved for shoppers with 10 or less items. The traditional rule is often hard to follow in practice, however, in part because plural nouns and mass nouns are similar in being divisible and in lacking distinct boundaries. For this reason, plurals and mass nouns are used in many of the same ways. Both can be used without determiners (I like apples, I like applesauce), and they both can take certain quantifiers like some and more (more apples, more applesauce). Less falls in the same class as some and more and is used in some well-established constructions where fewer would occur if the traditional rule were applied. Less than can be used before a plural noun that denotes a measure of time, amount, or distance: less than three weeks; less than $400; less than 50 miles. Less is sometimes used with plural nouns in the expressions no less than (as in No less than 30 of his colleagues signed the letter) and or less (as in Give your reasons in 25 words or less). And the approximator more or less is normally used after plural nouns as well as mass nouns: I have two dozen apples, more or less. To use fewer in such constructions sounds fastidious, so writers who follow the traditional rule should do so with caution.
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.