impervium
/ɪmˈpəːvɪəm/Originally and chiefly Science Fiction
noun
A virtually impenetrable or indestructible substance.
- Frequently (and earliest) in attributive use..
Origin
1930s. From imperv- + -ium.
- white admiral
- white Africa
- white African
- white alder
- white ale
- white alyssum
- white amur
- white ant
- white antimony
- white archangel
- White Army
- white arsenic
- white ash
- white-ash breeze
- white asparagus
- White Australia
- white-back
- white-backed
- white-backed vulture
- white backlash
- white backlasher
- whitebait
- whitebait dinner
- whitebait fritter
- whitebait season