1. Not able to be ascertained; resisting discovery
   - undiscoverable

See also: indeterminable, undeterminable

• portal hypertension
• portal site
• portal system
• portal tomb
• portal vein
• portamento
• portative
• portcullis
• Porte
• porte-cochère
• portend
• portent
• portentous
• portentously
• porter
• porter's beer
• porterage
• porterhouse
• porterhouse steak
• portfolio
• porthole
• Portia
• portia tree
• portico
• porticoed