/
ɔːgˈzɪlɪəri, 
ɒg-/
adj.
 providing additional help or support.
n.
 (pl. auxiliaries)
 an auxiliary person or thing. 
▸N. Amer. a group of volunteers who assist a church, hospital, etc. with charitable activities.
Etymology
ME: from L. auxiliarius, from auxilium ‘help’.