best friend

plural best friends

1. An especially close and trusted friend.

   I know you and Virginia are on best-friend terms.

   1994, Penny Vincenzi, Wicked Pleasures, →ISBN, page 46

   4 more examples

   A best friend is always there for you, even when no one else is.

   2001, Lauren, “To me a best friend is everything”, in Marilyn Kielbasa, Janet Claussen, editors, Listen for a Whisper: Prayers, Poems, and Reflections by Girls, →ISBN

   Being best friends means giving up control and allowing ourselves to become vulnerable.

   2004, Kenneth D. George, Keeping Mr. Right, →ISBN

   After all these years, he was still my best friend, and a few months later, he was my best man.

   2007 October 26, Elizabeth Welch, “The Avatar and the Fire Lord” (11:13 from the start), in Ethan Spaulding, director, Avatar: The Last Airbender, season 3 (Book Three: Fire), episode 6, spoken by Roku (James Garret)

   But my best friend, Gale Hawthorne, and his family will be depending on today’s haul and I can’t let them down.

   2009, Suzanne Collins, Catching Fire (The Hunger Games), New York, N.Y.: Scholastic Press, →ISBN, page 4

2. informalAn object or concept considered very useful or helpful to someone.

   An instructor informed us that in battle, your rifle is your best friend.

   2010, Art Seamans, I See, Said the Blind Man, AuthorHouse, →ISBN, page 48

   2 more examples

   You might even say, the bigger the problem, the greater your creative potential. The problem you're facing is your best friend because it will help to bring out the best in you.

   2005, Jeff Davidson, The Complete Idiot's Guide to Getting Things Done, Penguin, →ISBN, page 212

   As an entrepreneur, a conservative financial outlook is your best friend. Live to fight another day. Running a business also involves a host of legal issues. Talk to some people you respect and trust, get some recommendations, and hire a good lawyer and accountant.

   2006, Christopher Duncan, The Career Programmer: Guerilla^([sic]) Tactics for an Imperfect World, Apress, →ISBN

3. Used other than figuratively or idiomatically: see best, friend.

   Synonyms: boon companion, BFF, bestie, bosom friend