spineless :|ˈspaɪnləs| lacking determination and the willing | EngVestors Advanced

spineless :|ˈspaɪnləs|
lacking determination and the willingness to take risks;
soft, irresolute
бесхребетный, мягкотелый, бесхарактерный

She is too spineless to ask for more money;
My supervisor is a spineless person: he never stands behind his decisions;