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Synonyms

harmless

American  
[hahrm-lis] / ˈhɑrm lɪs /

adjective

  1. without the power or desire to do harm; innocuous.

    He looks mean but he's harmless; a harmless Halloween prank.
    Synonyms:
    benign, unobjectionable, innocent, mild, inoffensive

  2. without injury; unhurt; unharmed.

idioms

  1. hold harmless, to relieve from responsibility or liability for any damage or loss. Also save harmless.

harmless British  
/ ˈhɑːmlɪs /

adjective

  1. not causing any physical or mental damage or injury

  2. unlikely to annoy or worry people

    a harmless sort of man
"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

Other Word Forms

  • harmlessly adverb
  • harmlessness noun

Etymology

Origin of harmless

1250–1300; Middle English; harm, -less

Explanation

Things that can't hurt you are harmless. It might be hard for you to believe her when your sister tells you that her enormous pet snake is completely harmless. If your friend is scared of dogs, you can reassure her by saying, "Sure, he's 150 pounds and has a loud bark, but Fido is harmless!" Things that are safe or benign don't cause harm, and are therefore harmless, like your dad's harmless teasing or a compostable paper plate that's harmless to the environment. The word harmless originally meant "uninjured," or "not harmed," and came to mean "undamaged" by the end of the 1300s.

Keep Reading on Vocabulary.com

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"We know young people have been targeted online, and that means weapons are not harmless objects," she said.

From BBC • Apr. 3, 2026

At the same time, I have come to regard my tech tweaks as a relatively harmless nonhuman gesture.

From MarketWatch • Apr. 3, 2026

And yet, each of the pair is perhaps harmless without the other.

From The Wall Street Journal • Mar. 26, 2026

In a different timeline, this would be just harmless fun — a quirk of the president’s personality, nothing more.

From Salon • Mar. 19, 2026

At first, whatever lawlessness took place was relatively harmless.

From "1919 The Year That Changed America" by Martin W. Sandler

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

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