an·cil·lary /'an-sə-ˌler-ē, an-'si-lə-rē/ adj
1: having a subordinate, subsidiary, or secondary nature
ancillary functions
an ancillary agreement
2: serving as a supplement or addition
ancillary documents
3: directly related
ancillary claims
Merriam-Webster’s Dictionary of Law. Merriam-Webster. 1996.