es·sen·tial·ism 
(ĭ-sĕnshə-lĭz′əm)
(ĭ-sĕnshə-lĭz′əm)n.
The philosophical tenet that objects and classes of objects have essential and not merely accidental characteristics.
es·sential·ist adj.
- open-faced
- open fire
- openhanded
- openhandedly
- openhandedness
- openhearted
- openheartedly
- openheartedness
- open-hearth
- open-heart surgery
- open house
- opening
- open interval
- open-label
- open letter
- open listing
- open loop
- openly
- open market
- open marriage
- open meeting law
- open mike
- open-minded
- open-mindedly
- open-mindedness