an adult son residing with his parents; generally has not yet or can not come into family inheritance / a female servant working in a daimyō, ōoku, or other high-ranking house

room rent

at-home clothes

(Internet slang) dirty room

(physics, chemistry) atomic number

telephone number

a postal code, a zip code

number (on an athlete's uniform's back); jersey number, uniform number, player number, shirt number

PIN number, PIN

(computing) line number