It means eating an excessive amount, much more than normally a person would eat.
Mess
It can mean to eat a huge amount, more than you normally would.
The idiom means that the person over-indulged in whatever food or drink was provided, consuming more than was polite or prudent.
This is not an idiom because you can figure out what it means. When you see AS ___ AS ___ then you are looking at A Simile. This one is comparing someone who is happy to a happy pig in a muddy wallow, rolling around.
The idiom "bleed like a stuck pig" refers to the fact that pigs will bleed a lot when stabbed. It originated to make a point about vulnerable people.
Guinea pig is not an idiom. It is a type of small rodent that is often kept as a pet.I have a pet guinea pig.
Medicines and other things are often tested on small animals. Being a guinea pig means things are being tested on you or are asking you to try something out.
This isn't an idiom because you can figure out what it means without someone telling you. When you see "AS ____ AS _____" you're looking at A Simile - a type of comparison. They're comparing someone's happiness to the happiness of a pig wallowing around in the mud.
To "pig out" means to eat excessively during a meal. "I am so full! The buffet was so good that I just had to pig out!" "We are all so sick because we pigged out last night."
The idiom is "when pigs fly". Bacon comes from pigs, but bacon is not in the idiom. The idiom simply means, "impossible".
(UK, idiomatic, transitive) To do badly; to make a mess of.
Depends on the circumastances, when stressed/ excited / getting fed they make squeaking noises.