1. Not knowledgeable about something specified
   "a person unacquainted with our customs"
   - innocent 
2. Having little or no knowledge of
   "unacquainted with city ways"
   - unacquainted with, unfamiliar with

See also: unfamiliar, uninformed

• Thomas Wentworth Storrow Higginson
• Thomas Willis
• Thomas Wolfe
• Thomas Woodrow Wilson
• Thomas Wright Waller
• Thomas Young
• Thomism
• Thomomys
• Thomomys bottae
• Thomomys talpoides
• Thompson
• Thompson Seedless
• Thompson submachine gun
• Thomsen's disease
• Thomson
• Thomson's gazelle
• thong
• Thor
• Thor Hyerdahl
• thoracentesis
• thoracic
• thoracic actinomycosis
• thoracic aorta
• thoracic cavity
• thoracic duct