"Clam up" means to stop talking, especially when nervous, shy or unhappy. Example: A lot of men clam up when they are having emotional problems.
It means shut up!
It's not an idiom. To break camp means to break it up, to pack your things and leave the area. It can be used as slang, however, to mean a group "packing up" and leaving.
The idiom buck up means to cheer up. For example one might say "she began to buck up once I showed her some photographs of her children when they were younger."
If you mean a costume idea, you could dress up as a can - either a tin can or a trash can.
It means you stood up and started giving a speech.
I think you meant 'clam at high tide' or the full version 'happy as a clam at high tide'. This is an idiom/expression dating from the early 19th century. The expression means to be very joyful or content.
It means things are trustworthy.
say no to it
To make a mistake
About to be sold, or given up.
"Clam up" means to become quiet or refuse to speak, usually due to feeling nervous, secretive, or defensive.
To keep struggling and not give up.
flatter her to get something
It means shut up!
he suddenly turned up (to appear, emarge)
YES! I think... They can also clam up! -Happily!
to make something stronger ,,