In America, the word "scrubs" most commonly has one of the two meanings below:
1) The clothing worn by doctors and nurses during a surgery.
2) The act of cleaning vigorously by rubbing or grinding something against a surface in order to remove something.
The slang usage of the term, used to refer to a person, may be more common among certain areas in America than others. I rarely hear it in this part of the country, but would not be surprised to find that it is used all the time in another area. (This happens sometimes, as a slang term may be common within an entire region of the country, or within a culture, but almost unheard of in another region or culture).
Here are some examples of the two meanings that I mentioned at the start:
"The doctor put on her scrubs." = "The doctor put on the clothing that she wears during surgery."
"The nurse put on some scrubs." = "The nurse put on the clothing that they wear during surgery"
"He scrubs the dishes." = "He uses something to rub or grind off whatever is on the dishes."
"She scrubs her teeth." = "She uses a toothbrush to rub or grind off whatever is on her teeth."
"He scrubs his floor." = "He uses something to rub or grind off whatever is on his floor."
Notice that in each case above, you can substitute the word "cleans" for the word "scrubs." However, the word "scrubs" means that rubbing or grinding took place, while the word "cleans" can refers to any action that makes something clean.
For instance, "cleans" can include spraying, or wiping, or rubbing, or polishing, or grinding, etc.
"Scrubs" always includes rubbing or grinding.