名詞 fall out:

1. the radioactive particles that settle to the ground after a nuclear explosion
   同義詞：fallout, radioactive dust
2. any adverse and unwanted secondary effect
   同義詞：side effect, fallout

動詞 fall out:

1. have a breach in relations
2. come as a logical consequence; follow logically
   同義詞：follow
3. come off
   同義詞：come out
4. leave (a barracks) in order to take a place in a military formation, or leave a military formation
5. come to pass
   同義詞：happen, hap, go on, pass off, occur, pass, come about, take place

1. After a long drill he told the squad to fall out.
   操練了好半天之后，他讓這個班解散了。
2. The men fell out quickly after their march.
   士兵在列隊行進之後，很快便解散了。