igneous rock produced by eruption and solidified on or near the earth's surface; rhyolite or andesite or basalt; "volcanic rock includes the volcanic glass obsidian"
explosively unstable; "a volcanic temper"
relating to or produced by or consisting of volcanoes; "volcanic steam"; "volcanic islands such as Iceland"; "a volcanic cone is a conical mountain or hill built up of material from volcanic eruptions"
so remarkably different or sudden as to cause momentary shock or alarm; "Sydney's startling new Opera House"; "startling news"; "startling earthquake shocks"
without apparent forethought or prompting or planning; "an unplanned economy"; "accepts an unplanned order"; "an unplanned pregnancy"; "unplanned remarks"
the act of leaving secretly or without explanation
the event of passing out of sight
ceasing to exist; "he regretted the disappearance of Greek from school curricula"; "what was responsible for the disappearance of the rainforest?"; "the disappearance of resistance at very low temperatures"
characterized by undue haste and lack of thought or deliberation; "a hotheaded decision"; "liable to such impulsive acts as hugging strangers"; "an impetuous display of spending and gambling"; "madcap escapades"; (`brainish' is archaic)
characterized by unrest or disorder; "unquiet days of riots"; "following the assassination of Martin Luter King ours was an unquiet nation"; "spent an unquiet night tossing and turning"
taken unawares or suddenly and feeling wonder or astonishment; "surprised by her student's ingenuity"; "surprised that he remembered my name"; "a surprised expression"
moving quickly and lightly; "sleek and agile as a gymnast"; "as nimble as a deer"; "nimble fingers"; "quick of foot"; "the old dog was so spry it was halfway up the stairs before we could stop it"
not prudent or wise; "very imprudent of her mother to encourage her in such silly romantic ideas"; "would be imprudent for a noneconomist to talk about the details of economic policy"- A.M.Schlesinger