I shudder/dread to think humorous spoken language informal
Said when you mean that you don't want or are afraid to think about something because it is too unpleasant.
This train is too crowded! I dread to think what would happen if there really was an infected person here.
I shudder to think what would have happened if the driver hadn’t swerved in time.
I dread to think what would have happened if I hadn’t been rescued in time.
The origin of this phrase is not clear.
This phrase emphasize that Christmas takes place once a year time, so you should grab this chance to indulge yourself and be good to others.
I've eaten a little more than usual as today is Christmas and Christmas comes but once a year, right?