1. in a precarious or risky situation
you're skating on thin ice
To be 'on thin ice' is to be in a risky or precarious situation that may have serious consequences. You can say someone is 'walking on thin ice', 'treading on thin ice' or 'skating on thin ice' and it means the same thing, that they are doing something risky. You will normally hear this expression used as a warning. "You are on thin ice if I were you I would stop lying." "He was on thin ice before and he knew he wouldn't get away with it this time."