an ‧ cil ‧ la ‧ ry /ænˈsɪləri $ ˈænsəleri/ BrE AmE adjective
[ Date: 1600-1700 ; Language: Latin ; Origin: ancilla 'female servant' ]
1 . ancillary workers/staff etc workers who provide additional help and services for the people who do the main work in hospitals, schools etc
2 . formal connected with or supporting something else, but less important than it:
Agreement was reached on several ancillary matters.