1. Situated at or extending to great depth; too deep to have been sounded or plumbed
   "remote and unsounded caverns"
   - profound, unfathomed, unplumbed 
2. Not made to sound
   "in French certain letters are often unsounded"
   - silent

See also: deep, inaudible, unhearable

• pressure level
• pressure point
• pressure sensation
• pressure sore
• pressure suit
• pressure unit
• pressure-cook
• pressure-feed lubricating system
• pressure-wash
• pressurisation
• pressurise
• pressurised water reactor
• pressurization
• pressurize
• pressurized water reactor
• presswork
• prestidigitation
• prestidigitator
• prestige
• correlational
• correlational analysis
• correlational statistics
• correlative
• correlatively
• correlativity