BFF
- 1Initialism of best friend forever.
Maya invited her BFF to be maid of honor at the wedding.
The two became BFFs after spending a whole summer at camp together.
Note
An abbreviation that has hardened into a noun in its own right, with an ordinary plural: BFFs, no apostrophe. Melissa Bolton-Klinger and Jayan Kalathil's Generation Change (2013) pictures a pub crawl with "your BFFs." The "forever" still carries weight. The full phrase means a close, trusted friend of long standing, not just this month's companion, so the word quietly claims history as well as warmth.
- 2Initialism of backend for frontend.
The architects introduced a BFF to keep API responses tailored and lean for the web client.
Rather than one monolithic gateway, the platform now runs separate BFFs for its iOS and Android apps.
Note
A software-engineering pattern: each frontend client gets its own dedicated backend service. That service shapes its API and payloads to what the client needs, instead of exposing one general-purpose interface. Inside the expansion, backend is the closed-up spelling of back end, and both spellings are in use. Context keeps it apart from the friendship meaning. The two senses rarely share a conversation.
Practice
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