a dental 'assistant' [=a person whose job is to help a dentist]
She works as a 'sales assistant' [='salesclerk'] at Macy's.
a wealthy executive who has a personal 'assistant'
(..) This one did. - Will you come? - Who's on forensics? - Anderson. - He doesn't work well with me. - Well, he won't be your assistant. - I need an assistant. Will you come? Not in a police car, I'll be right behind. Thank you. Brilliant! Yes! (..)2010 TvShow: Sherlock Title: A Study in Pink Season: 1 Episode 1