flex·i·tar·i·an 
(flĕk′sĭ-târē-ən)
(flĕk′sĭ-târē-ən)n.
One who normally maintains a vegetarian diet but occasionally makes exceptions and eats meat or fish.
adj.
Of or relating to a diet that is primarily vegetarian but includes meat or fish on occasion.
[FLEXI(BLE) + (VEGE)TARIAN.]