Drop out and Sign off

Drop out verb - Give up in the face of defeat of lacking hope; admit defeat.

Sign off and drop out are semantically related In some cases you can use "Sign off" instead a verb "Drop out".

Sign off verb - Cease broadcasting; get off the air; as of radio stations.

Drop out and sign off are semantically related in resign topic. Sometimes you can use "Drop out" instead a verb "Sign off", if it concerns topics such as give up responsibility.