Assistant is never abbreviated as "ass". The abbreviation for administrative assistant is admin. asst.

Administrative assistant is another title for secretary.

An administrative assistant is 'un assistant / une assistante administrative' in French. Probably we would just say 'assistant' or 'secrétaire', instead of the full title.

An alternate term for "secretary" could be "administrative assistant" or "clerk."

These are both office jobs that require attention to detail. The administrative assistant may do some bookkeeping and the bookkeeper may do some administrative assistant work.