A harbinger is just a messenger or forewarning of something. There can be harbingers of anything really.
I imagine the ending "...of doom" is used so often because doom is something that usually slowly and/or ominously builds over time and as such, there is usually a harbinger or warning of some kind - not necessarily so with other things maybe.
Partly a guess I admit.
I imagine the ending "...of doom" is used so often because doom is something that usually slowly and/or ominously builds over time and as such, there is usually a harbinger or warning of some kind - not necessarily so with other things maybe.
Partly a guess I admit.