(idiomatic) To wind up in an unexpected situation which is, inadvertently, invisible to or not handled by whatever process one had hoped to be subject to; to be overlooked.

(intransitive, dated) To be destined to happen to someone or to fall in someone's possession.

(idiomatic) Of something desirable, to be received by someone with little or no effort or by chance.

(dated, idiomatic) To embrace someone affectionately or thankfully.

(idiomatic) To become the possession of, or be discovered by, an unfriendly third party.

colony collapse disorder

present participle of fall on hard times

To experience a difficult period, especially financially.

present participle of fall from grace

Of words, an idea, etc.: to go unheeded.