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definitions

less

[les]
See more synonyms for less on Thesaurus.com
adverb, a compar. of little with least as superl.
  1. to a smaller extent, amount, or degree: less exact.
  2. most certainly not (often preceded by much or still): He could barely pay for his own lodging, much less for that of his friend.
  3. in any way different; other: He is nothing less than a thief.
adjective, a compar. of little with least as superl.
  1. smaller in size, amount, degree, etc.; not so large, great, or much: less money; less speed.
  2. lower in consideration, rank, or importance: no less a person than the manager.
  3. fewer: less than a dozen.
noun
  1. a smaller amount or quantity: Hundreds of soldiers arrived, but less of them remained.
  2. something inferior or not as important: He was tortured for less.
preposition
  1. minus; without: a year less two days; six dollars less tax.
Idioms
  1. less than, by far short of being; not in the least; hardly at all: The job is less than perfect.

Origin of less

before 900; Middle English; Old English lǣs (adv.), lǣssa (adj.); cognate with Old Frisian lês (adv.), lêssa (adj.). See least
Can be confusedfewer less (see usage note at the current entry)

Synonyms for less

See more synonyms for on Thesaurus.com
4. See small.

Usage note

Even though less has been used before plural nouns ( less words; less men ) since the time of King Alfred, many modern usage guides say that only fewer can be used in such contexts. Less, they say, should modify singular mass nouns ( less sugar; less money ) and singular abstract nouns ( less honesty; less love ). It should modify plural nouns only when they suggest combination into a unit, group, or aggregation: less than $50 (a sum of money); less than three miles (a unit of distance). With plural nouns specifying individuals or readily distinguishable units, the guides say that fewer is the only proper choice: fewer words; fewer men; no fewer than 31 of the 50 states.
Modern standard English practice does not reflect this distinction. When followed by than, less occurs at least as often as fewer in modifying plural nouns that are not units or groups, and the use of less in this construction is increasing in all varieties of English: less than eight million people; no less than 31 of the 50 states. When not followed by than, fewer is more frequent only in formal written English, and in this construction also the use of less is increasing: This year we have had less crimes, less accidents, and less fires than in any of the last five years.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for less than

below, lesser, subject, subordinate, under, underneath
British Dictionary definitions for less than

less

determiner
    1. the comparative of little (def. 1) less sugar; less spirit than before
    2. (as pronoun; functioning as sing or plural)she has less than she needs; the less you eat, the less you want
  2. (usually preceded by no) lower in rank or importanceno less a man than the president; St James the Less
  3. no less informal used to indicate surprise or admiration, often sarcastic, at the preceding statementshe says she's been to Italy, no less
  4. less of to a smaller extent or degreewe see less of John these days; less of a success than I'd hoped
adverb
  1. the comparative of little (sense 1)she walks less than she should; less quickly; less beautiful
  2. much less or still less used to reinforce a negativewe don't like it, still less enjoy it
  3. think less of to have a lower opinion of
preposition
  1. subtracting; minusthree weeks less a day

Word Origin for less

Old English lǣssa (adj), lǣs (adv, n)

usage

Less should not be confused with fewer. Less refers strictly only to quantity and not to number: there is less water than before. Fewer means smaller in number: there are fewer people than before
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for less than

less

Old English læs (adv.), læssa (adj.), comparative of læs "small;" from Proto-Germanic *lais-izo "smaller" (cf. Old Saxon, Old Frisian les "less;" Middle Dutch lise "soft, gentle," German leise "soft"), from PIE root *leis- "small" (cf. Lithuanian liesas "thin"). Formerly also "younger," as a translation of Latin minor, a sense now obsolete except in James the Less. Used as a comparative of little, but not related to it. The noun is Old English læsse.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with less than

less than

Not at all or hardly at all. For example, He had a less than favorable view of the matter, or She had a less than adequate grasp of the subject. This expression uses less in the sense of “a smaller quantity, number, or extent than is implied,” a usage dating from about a.d. 1000. The same sense appears in less than no time, a hyperbolic term for a very short time (as in Don't worry, he'll be here in less than no time) that dates from about 1800.

less

In addition to the idiom beginning with less

  • less than

also see:

  • couldn't care less
  • in (less than) no time
  • more or less
  • much less
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.