Synonyms for Coincident (same or very similar meaning)
WordNet sense 1 (occurring or operating at the same time):
coincidental, concurrent, simultaneous, coinciding, cooccurring, co-occurrent
WordNet sense 2 (occurring or existing at the same time or having the same period or phase):
synchronous, synchronal, synchronic
WordNet sense 3 (coinciding when superimposed):
congruent
From the ODE community, based on WordNet
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