What is the meaning of Fall_out?

Synonym of falling out (rift following a disagreement or quarrel)

To come out of something by falling.

To cease to be on friendly terms.

To leave one's place in the current formation of ranks in order to take one's place in a new formation.

To leave one's current location to report for duty at a new location.

To pass out.

To turn out, happen.

Source: wiktionary.org