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'
(..) ...you will witness the birth of a new fusion-based energy source. Safe, renewable energy and cheap electricity for everyone. And now let me introduce my assistants. These four actuators were developed and programmed... ...for the sole purpose of creating successful fusion. (..)2004 Spider-Man 2