It means that you are in"over your head," or in a situation you can't handle. It's similar to "in hot water." The image is of you over your head, in deep water, and having to swim for your life.
That's not an idiom. It's just saying that someone's body is beneath the surface of the water.
It refers to a ship that is not going anywhere and is dead in the water. If you are dead in the water, you are at a stop and unable to proceed.
wait for a long time
It means secretly.
Nothing that I have ever heard. "Under the weather" is an idiom, but there's no anger in the phrase.
This is not an idiom I have ever heard. Perhaps you mean water cooler talk, which means chat that might occur between workers at the water cooler or anywhere else.
Went under is used to mean they have failed, as in drowning. A business that went under is one that has closed or gone bankrupt.
This is not an idiom. An idiom is an expression whose meaning cannot be deduced from its elements. To go through fire and water for someone is easily understood to mean to make a special effort and to undergo difficulties for that person's sake.
Er ... what? Are you asking what "under one's wing" means? Here's a link.
It is not an idiom, it is fact. A hose can be used for a water level with hundreds of feet between the two points. As long as two bodies of water are connected somehow, they will be at the same level. As an idiom, it would mean a person tends to seek out people they feel are equal or have the same point of view.
First, when you see the phrase AS ___ AS ___ it is A Simile instead of an idiom. It is easy to figure out the meaning of a simile. Water flows quickly, so the simile means that whatever it is, it's as fast as water flowing.
It depends on what the rest of the phrase said. "Everything under the sun" is a figurative way of saying "everything," while "under the sun" alone would mean out in the sunlight.
The idiom, "You must have been under a rock" means that you must have been away, in hiding or had no contact with civilization to miss this big eventFor example 'You didn't hear about him? You must have been living under a rock to miss that!'
Having already been judged badly, and having to get out from under the cloud before proceeding.to be under suspicion or in disgrace; to be in disfavor.
You can't show me anything that I haven't seen already.?