adjutant (n.) Look up adjutant at Dictionary.com
"military officer who assists superior officers," c. 1600, from Latin adiutantem (nominative adiutans), present participle of adiutare "to give help to, help zealously, serve," frequentative of adiuvare (past participle adiutus) "help, assist, aid, support," from ad- "to" (see ad-) + iuvare "to help, give strength, support," perhaps from same root as iuvenis "young person" (see young).