1. A very well-known public figure 
2. A brand name that is well known to the great majority of households

Derived forms: household names

• most valuable player
• most-favored-nation
• most-favoured-nation
• most-valuable
• mostaccioli
• mostly
• Mosul
• mot
• mot juste
• MOT test
• Motacilla
• Motacillidae
• mote
• motel
• motel room
• motet
• moth
• moth bean
• moth miller
• moth mullein
• moth orchid
• moth plant
• moth-eaten
• moth-resistant
• mothball