1
general::
Fail, miscarry, as in The proposed amendment fell through, or I hope our plans won't fall through. [Late 1700s]
American Heritage Idioms
2
general::
Phrase(s): fall through
[for something, such as plans] to fail. • Our party for next Saturday fell through. • I hope our plans don’t fall through., Phrase(s): fall through something
to fall and break through something. • One of the skaters fell through the thin ice. • A number of hailstones fell through the roof of the greenhouse.
McGrawhill's American Idioms And Phrasal Verbs