why is a tooth brush, called a tooth(singular) brush, when it cleans teeth??just a daft one for you!!?

I'm a registered Dental Assistant in the state of California and I don't know the answer to that one- sorry.

Because it was invented in West Virginia, where "Nice tooth" is a good pick-up line.

Because it was invented in Kentucky.

Because it was invented in Arkansas.

Because it was invented in Alabama.

Because it was invented in Maine.

Because it was invented by a blonde.

Because it was invented by a hillbilly.

Because it was invented by a Willie Nelson roadie.

Because it was invented by an NHS dentist in the UK.

Because you are supposed to brush one tooth at the time.

Because they didn't want to make people who have only one tooth feel bad.

Because the original toothbrush was a frayed twig and you could only brush one tooth at a time.

Why is it called a "pair" of pants?

Serious answers:

Compound words in English are almost always if not always formed with the singular word, such as mousetrap, football, bookcase, bedroom and toothbrush

http://www.loc.gov/rr/scitech/mysteries/tooth.html

OK this may sound false, but I believe it's true and I'll give my explanation at the end. Tooth Brush sounds better than teeth brush (It flows more smoothly) And I'll give you a FACT Butterflies used to be called Flutter Bys but that was to difficult for people to pronounce so they changed it to butterflies. On that note tooth brush also sounds better sort of silly but possibly true..

For the same reason a tooth pick isn't called a teeth pick.

because the toothbrush was invented in West Virginia

they usually only have a tooth

Because when they invented it people only had 1 tooth left! there was no such thing as teeth.

Because it cleans each tooth individually ? Who knows ;o)

Probably because the inventer had only one tooth.

you brush one tooth at a time

Becoz teeth brush dont sound rite