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  • sign-in
    sign-in
    noun
    an act, an instance, or a time of signing in.
  • sign in
    sign in
    verb
    to sign or cause to sign a register, as at a hotel, club, etc
Synonyms

sign-in

American  
[sahyn-in] / ˈsaɪnˌɪn /

noun

  1. an act, an instance, or a time of signing in.

sign in British  

verb

  1. to sign or cause to sign a register, as at a hotel, club, etc

  2. to make or become a member, as of a club

"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
sign in Idioms  

  1. Record one's arrival by signing a register, as in He signed in both himself and his wife. [c. 1930] For the antonym, see sign out.

Etymology

Origin of sign-in

First recorded in 1945–50; noun use of verb phrase sign in

Compare meaning

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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 shouldn’t have to sign-in every time we fire up the laptop and other devices.

From The Wall Street Journal • Apr. 15, 2026

It provides a single sign-in portal that verifies and grants appropriate access to various programs.

From Barron's • Feb. 5, 2026

Preserving content on Google Photos requires a specific sign-in.

From Seattle Times • Nov. 27, 2023

That can include the author's relationship with other online accounts, their sign-in activity, review history, and any unusual behaviour.

From BBC • Jun. 12, 2023

Jay gives the lady at the sign-in desk Aunt Pooh’s real name—Katricia Bordeaux.

From "On the Come Up" by Angie Thomas

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.