1867, from Swedish dynamit, coined 1867 by its inventor, Swedish chemist Alfred Nobel (1833-1896), from Greek dynamis "power" (see dynamic (adj.)) + -ite (2). Figurative sense of "something potentially dangerous" is from 1922. Positive sense of "dynamic and excellent" by mid-1960s, perhaps originally Black English.
1881, from dynamite (n.). Related: Dynamited; dynamiting.
(also dyno-mite) Excellent; superior; super: ''Dynamite. I knew we'd get along/ DYN-OMITE! The Blammo 12-gauge has a precision-cast hollow-core slug with stabilization tail fins for accuracy at long range