From Longman Dictionary of Contemporary Englishdieticiandi‧e‧ti‧cian, dietitian /ˌdaɪəˈtɪʃən/ noun [countable] BODFNsomeone who is trained to give people advice about what it is healthy for them to eat and drink
Examples from the Corpus
dietician• Tony Carpenter, a dietician, says it's vital they drink as much fluid as they can get.• Various paramedical staff may be members of the team, commonly the physiotherapist and dietician, although others may be involved.• Speaking of carrots, there is another important role the caddie performs nowadays, that of dietician.• I want the dietician to see her.• The dietician at the hospital will be able to help you.• The dietician will give advice so that each individual is given adequate nourishment. 