1. In isolation and without reference to anything else 
2. In a vacuum

Encyclopedia: In vacuo

• portress
• Portsmouth
• Portugal
• Portuguese
• Portuguese cypress
• Portuguese escudo
• Portuguese Guinea
• Portuguese heath
• Portuguese man-of-war
• Portuguese monetary unit
• Portuguese Republic
• portulaca
• Portulaca grandiflora
• Portulaca oleracea
• Portulacaceae
• Portunidae
• Portunus
• Portunus puber
• portwatcher
• Porzana
• Porzana porzana
• POS
• pos tagger
• posada
• pose