supernumerary, special, supererogatory, redundant, other, superfluous, excess, unnecessary, surplus, additional, more...

basic, standard, normal, essential, minimal

extrcheese, extrsauce, extrtoppings, extrpickles, extrbacon, extronions, extrmayo, extrlettuce, extrketchup, more...

postage, optional, double, best, new, perbunan, late, first, equal, introversion, special

more than usual,   additional amount,   something more,   actor with no lines,   uncredited actor,   an additional,   actor without lines,   walk-on part,   over and beyond,   crowd scene actress