untimely

lament, mourn
Few will mourn his passing.

mark
Her death marks the passing of an era.

note

the passing of the years, the passing of time
The wood darkens with the passing of time.

Passing is used with these nouns:
acquaintance, comment, craze, fad, familiarity, fashion, grade, interest, mention, minute, moment, nod, reference, remark, resemblance, scenery, ship, stranger, thought, traffic, train, vehicle, waiter, waitress