verb. Present participle of coincide.

noun. Act or situation by which things coincide; coincidence.

adjective. occurring or operating at the same time

"Salter, one of the pioneers of behavior therapy, distinguished between “inhibitory” and “excitatory” behaviors, the latter term coinciding with what we now call assertiveness."

synchronal  synchronic  synchronous  

abiding  biding  chiding  colliding  confiding  

accordant  affirmative  agreeable  agreeing  answerable  

coincide