We don't have synonyms for back seats yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are back seat, backseats and backseat.
(n) :
(informal, especially in the expression take a back seat) A lesser or inferior position; a position of deliberate noninvolvement, in which decision-making or leadership is left to others.
(n) :
(informal, especially in the expression take a back seat) A lesser or inferior position; a position of deliberate noninvolvement, in which decision-making or leadership is left to others.