Abstract: A spinneret having octagonally-shaped orifices for producing yarn filaments having a characteristic cross-section and improved cross-sectional fidelity. The filament cross-section is characterized by generally symmetrical rectangular sub-sections each having four lobes and joined one to the other by a central bridging portion connecting the short facing sides of the sub-sections. This cross-section has increased surface area and remains substantially constant throughout the length of the filament whereby reduced air pressure is required when using the filament in air jet looms.