aqua, agua
Wash is a four letter word meaning "to clean with water".
swim?
tide
A four letter word starting with the letter a is able.
It depends on what you mean by 'four letter word'. Thea has four letters, so yes it is. It is not a swear word, so it's not that kind of 'four letter word'.
Wash is a four letter word meaning "to clean with water".
Wash is a four letter word meaning "to clean with water".
A "bay" is a small protected body of water that is a four-letter word.
scum
best
Flow or tide
tide
fish
swim?
Sink
Wash.
One possibility is the word pipe. For example, water flows threw pipes.