Etymology

Medieval Latin coincidere: to occupy the same place or time. The ordinary sense is older than the uncanny one. Two things can fall together without a third thing arranging them.1

Semantic range

Unsprising overlap, surprising overlap, personal meaning, proposed acausal order. Meaning is not the same claim as cause.

What the gloss loses

Calling something ‘just coincidence’ can be a dismissal. Calling it ‘not coincidence’ can be a promotion. Both skip the looking.

Misuse

Using coincidence as a verdict instead of a description of timing.