highly or violently reactive; "sensitive and highly unstable compounds"
disposed to psychological variability; "his rather unstable religious convictions"
lacking stability or fixity or firmness; "unstable political conditions"; "the tower proved to be unstable in the high wind"; "an unstable world economy"
likely to change frequently often without apparent or cogent reason; variable; "inconstant affections"; "an inconstant lover"; "swear not by...the inconstant moon"- Shakespeare