1. Of or relating to or having a fenestra 
2. Of or relating to windows

See also: fenestra, window

• unprepared
• unprepossessing
• unpresentable
• unpresidential
• unpressed
• unpretending
• unpretentious
• unpretentiously
• unpretentiousness
• unpreventable
• unpriestly
• unprincipled
• unprintable
• open-end wrench
• open-ended
• open-eyed
• open-face sandwich
• open-faced
• open-heart surgery
• open-hearth
• open-hearth furnace
• open-hearth process
• open-minded
• open-mindedly
• open-mindedness