If someone who is in deep water treads water, they float in an upright position by moving their legs slightly.
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tread water
phrase
If you say that someone is treading water, you mean that they are in an unsatisfactory situation where they are not progressing, but are just continuing doing the same things.
I could either tread water until I was promoted, or I could change what I was doing.
See full dictionary entry for tread
tread water in British English
to stay afloat in an upright position by moving the legs in a walking motion
See full dictionary entry for tread
tread water in American English
1. Swimming
to keep the head above water and the body upright without propelling oneself forward, by moving the legs and arms back and forth
2.
to make no progress
pt. & pp. now usually tread verb transitive, See full dictionary entry for tread
tread water
to be in an unsatisfactory situation where you are not progressing, but are just continuingdoing the same things
I could either tread water until I was promoted, which looked to be a few years away,or I could change what I was doing.
Examples of 'tread water' in a sentence
tread water
Now Bagado and I both had our millstones and Bagado was going to have to tread water with his while I got out from under my own.
Robert Wilson A DARKENING STAIN (2002)
They drew even with the first of a series of small coves, and stopped, letting the others catch up and tread water a moment.