Zip your lip If someone tells you to zip your lip, they want to to shut up or keep quiet about something. (‘Zip it’ is also used.)
Zero tolerance If the police have a zero tolerance policy, they will not overlook any crime, no matter how small or trivial.
Zigged before you zagged If you did things in the wrong order, you zigged before you zagged.
Zip it This is used to tell someone to be quiet.
Your belly button is bigger than your stomach If your belly button is bigger than your stomach, you take on more responsibilities than you can handle.
Your call If something is your call, it is up to you to make a decision on the matter.
Your name is mud If someone’s name is mud, then they have a bad reputation.
Your sins will find you out This idiom means that things you do wrong will become known.
Zero hour The time when something important is to begin is zero hour.
You’ve made your bed- you’ll have to lie in it This means that someone will have to live with the consequences of their own actions.