(Internet) Abbreviation of Facebook.

(soccer) Initialism of fullback. / Initialism of friendship book. / (military) Initialism of firebase. / (military) Initialism of forward base.

Abbreviation of February.

Initialism of fetal blood sampling. / (medicine) Initialism of fasting blood sugar. / Initialism of fetal bovine serum. / (military) Initialism of forward-based system.

(American football) Initialism of Football Bowl Subdivision.

plural of FB

(US) Initialism of Federal Bureau of Investigation. / (Britain) Federation of British Industry (1916–1965), forerunner of CBI (Confederation of British Industry).

Fixed-bit index. / (US, humorous) Female body inspector.

(uncountable) Initialism of fermentation biotechnology. / (countable, property law, England & Wales) Initialism of farm business tenancy.

Initialism of full-body sensual massage.