1. Not ostentatious
   "his unostentatious office"; "unostentatious elegance"
   - unpretentious, unpretending 
2. Exhibiting restrained good taste
   - understated, unpretentious

See also: quiet, restrained, tasteful

Antonym: ostentatious

• OPV
• opéra bouffe
• or
• OR circuit
• or else
• OR gate
• or so
• ora
• orach
• orache
• oracle
• Oracle of Apollo
• oracle of Delphi
• oracular
• orad
• Oradexon
• oral
• oral cancer
• oral cavity
• oral communication
• oral contraception
• oral contraceptive
• oral contraceptive pill
• oral contract
• oral exam