simulalia
The act of two people uttering the identical word or phrase, in the exact tone and cadence, to convey the same thought, at precisely the same moment.
They were so close, their perceptions and observations were linked in such harmonious synchronicity, that many times a day they spoke in perfect unison, often to the amused astonishment of those listening. "We need a word for it" she suggested. And an instant later, they both said "simulalia".