best friend

noun

plural best friends

1

: a person's closest and dearest friend

She's my best friend.

We have been best friends since high school.

2

: a person's most desirable or valuable possession or resource

Diamonds may be a girl's best friend, but gold is more affordable.

—William Giese

Lycra-cotton leggings and tunic tops are the pregnant woman's best friend, sartorially speaking.

—Anne Reeks

When cops bang on the door, the toilet is a drug dealer's best friend.

—Frederick Kaufman

Examples of best friend in a Sentence

Recent Examples on the Web

Rachel Sennott created the comedy and costars as her estranged best friend, Maia, who tries to leverage Tallulah’s social media infamy into a legitimate career. —Patrick Ryan, USA Today, 2 Jan. 2026

His childhood best friend and sometimes-lover, Rachel Mizler (Odessa A’zion), gets swept up in his hijinks, as does his temperamental foil of a friend, Wally (Tyler the Creator). —Alexandra Jhamb Burns, Condé Nast Traveler, 2 Jan. 2026

Lloromannic, a little devil duo consisting of Berry, a demon boy with big ram horns, and Cherry, his cunning demon girl counterpart; Lovelymocha, best friend of Cinnamoroll; U*SA*HA*NA is a lively, colorful rabbit. —Angela Andaloro, PEOPLE, 1 Jan. 2026

Dustin excels in college and stays best friends with Steve. —Maggie Fremont, Vulture, 1 Jan. 2026

Word History

First Known Use

13th century, in the meaning defined at sense 1

Phrases Containing best friend

• man's best friend

Rhymes for best friend

• amend
• append
• ascend
• attend
• backend
• befriend
• boyfriend
• commend
• compend
• contend
• defend
• depend