Synonyms for Groundbreaking (same or very similar meaning)
WordNet sense 1 (being or producing something like nothing done or experienced or created before):
innovative, innovational
WordNet sense 2 (being or productive of something fresh and unusual; or being as first made or thought of):
original
WordNet sense 3 (the ceremonial breaking of the ground to formally begin a construction project):
groundbreaking ceremony
From the ODE community, based on WordNet
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