A hygienist, in the way you will actually meet the word, is the person at the dentist’s who cleans your teeth, checks your gums, and shows you how to brush and floss so trouble does not start. They work with the dentist but they are not the dentist — they do not usually fill holes or pull teeth. The full name is often dental hygienist; people shorten it to hygienist when you are already talking about the clinic. In public-health English a hygienist can also mean a specialist in hygiene more widely, but learners almost always meet the dental job. It is a job title, a little formal, used on clinic doors and appointment cards.