aide-de-camp
Concise Oxford English Dictionary © 2008 Oxford University Press:
aide-de-camp /ˌeɪddəˈkɒ̃/
▶noun (pl. aides-de-camp pronunc. same) a military officer acting as a confidential assistant to a senior officer.
– origin C17: from Fr., ‘camp adjutant’.
'aide-de-camp' also found in these Oxford entries:

