incidental Antonyms

necessary basic intentional main primogenial primary primal prerequisite prepense prominent quintessential ranking reassign significant strategic structural substantial premier premeditated major mandatory mathematical mayoral nonacid pandemic paramount parlous pertinent plasmic predestined predominant preeminent substantive supreme climactic superordinate larger biochemical greater life-and-death life-or-death built-in inbuilt native-born number one greatest much needed not to be sneezed at firebase bare bones