immiscible
\ ih-MIS-uh-buhl \ , adjective;
1.not miscible; incapable of being mixed.
Quotes:
Yosil is with me now, our borders overlapping in unhappy swirls, like immiscible fluids.
-- David Brin, "Kiln People" , 2002
The youngest one wore its hair in a style popularized by a sitcom that took as its subject three roommates of seemingly immiscible temperaments and their attempts to make their fortune in this contusing city.
-- Colson Whitehead, "Zone One" , 2011
Origin:
Immiscible is derived from the prefix im- which is a variant of in- meaning having a negative force, as in the words immoral and indefensible . The word miscible means "capable of being mixed" and is used primarily in chemistry and physics.
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