adjective (used predicatively)

separate, apart, or isolated from others: I want to be alone.
to the exclusion of all others or all else: One cannot live by bread alone.
unique; unequaled; unexcelled: He is alone among his peers in devotion to duty.


solitarily; solely: She prefers to live alone.
only; exclusively.
without aid or help: The baby let go of the side of the crib and stood alone.


    leave alone,
    1. to allow (someone) to be by himself or herself: Leave him alone—he wants to rest.
    2. to refrain from annoying or interfering with: The youngsters wouldn't leave the dog alone, and he finally turned on them.
    let alone,
    1. to refrain from annoying or interfering with.
    2. not to mention: He was too tired to walk, let alone run.
    let well enough alone, to be satisfied with the existing situation; refrain from attempting to change conditions: Marriages are often destroyed by relatives who will not let well enough alone.

Origin of alone

1250–1300; Middle English al one all (wholly) one
Related formsa·lone·ness, noun

Synonyms for alone

Synonym study

1. Alone, lone, lonely, lonesome all imply being without companionship or association. Alone is colorless unless reinforced by all; it then suggests solitariness or desolation: alone in the house; all alone on an island. Lone is somewhat poetic or is intended humorously: a lone sentinel. Lonely implies a sad or disquieting feeling of isolation. Lonesome connotes emotion, a longing for companionship.

Antonyms for alone

1. accompanied.

Usage note

7, 8. See leave1. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for let alone

decontrol, denationalize

British Dictionary definitions for let alone


adjective, adverb (postpositive)

apart from another or others; solitary
without anyone or anything elseone man alone could lift it
without equal; uniquehe stands alone in the field of microbiology
to the exclusion of others; onlyshe alone believed him
leave alone, leave be, let alone or let be to refrain from annoying or interfering with
leave well alone, leave well enough alone, let well alone or let well enough alone to refrain from interfering with something that is satisfactory
let alone much less; not to mentionhe can't afford beer, let alone whisky

Word Origin for alone

Old English al one, literally: all (entirely) one
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 let alone


adj., adv.

c.1300 contraction of all ane, from Old English all ana "unaccompanied, all by oneself," from all "all, wholly" (see all) + an "one" (see one). Similar compounds are found in German (allein) and Dutch (alleen).

Online Etymology Dictionary, © 2010 Douglas Harper

Idioms and Phrases with let alone

let alone


See leave someone alone.


Not to mention, as in We have no room for another house guest, let alone an entire family. [c. 1800]


see go it alone; leave someone alone; leave well enough alone; let alone.

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.