The definition of a harbinger is something or someone who announces that something or someone is coming.
(noun)Thunder is an example of a harbinger of a rainstorm.
See harbinger in Webster's New World College Dictionary
noun
Origin: ME herbergeour (with intrusive -n-) < OFr herbergeor, provider of lodging < herberge, a shelter < Frank (or OHG) heriberga, shelter for soldiers < heri, army (see harry) + berga, a shelter < bergan, to protect: see bury
transitive verb
See harbinger in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English herbengar, person sent ahead to arrange lodgings
Origin: , from Old French herbergeor
Origin: , from herbergier, to provide lodging for
Origin: , from herberge, lodging
Origin: , of Germanic origin; see koro- in Indo-European roots
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