Merriam-Webster's Collegiate® Dictionary, 11th Edition
HARBINGER
I. noun
Etymology: Middle English herbergere, from Anglo-French, host, from herberge camp, lodgings, of Germanic origin; akin to Old High German heriberga
Date: 14th century
a person sent ahead to provide lodgings,
2. one that pioneers in or initiates a major change ; precursor , one that presages or foreshadows what is to come, see: forerunner
II. transitive verb
Date: 1646
to be a harbinger of ; presage