Occurring or existing concurrently; attendant. See Synonyms at contemporary.
n.
One that occurs or exists concurrently with another.
[Late Latin concomitns, concomitant-, present participle of concomitr, to accompany : Latin com-, com- + Latin comitr, to accompany (from comes, comit-, companion; see ei- in Indo-European roots).]
associate – any event that usually accompanies or is closely connected with another; “first was the lightning and then its thunderous associate”
background – relatively unimportant or inconspicuous accompanying situation; “when the rain came he could hear the sound of thunder in the background”
Adj.
1.
concomitant – following or accompanying as a consequence; “an excessive growth of bureaucracy, with attendant problems”; “snags incidental to the changeover in management”; “attendant circumstances”; “the period of tension and consequent need for military preparedness”; “the ensuant response to his appeal”; “the resultant savings were considerable”