1. An acronym or abbreviation so old or familiar that few remember what its letters stand for, such as radar or BASIC (anachronistic + acronym)

Encyclopedia: Anacronym

• ossicular
• ossiculate
• ossiculum
• ossiferous
• ossification
• ossified
• ossifrage
• ossify
• osso buco
• ossuary
• Ostariophysi
• osteal
• Osteichthyes
• osteitis
• osteitis deformans
• ostend
• ostensible
• ostensibly
• ostensive
• ostensive definition
• ostensively
• ostensorium
• ostentate
• ostentation
• ostentatious