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odd number of aperture blades and blade shape usually produce what you're describing. polygonal aperture with an odd number of blades like 5-7. most famous lens goes up to 9. cooke, angenieux and zeiss were all creating these types of lenses in the 70s. there were a lot of them earlier, but a different shaped star burst / bokeh and flaring became popular in the 70s. earlier lenses had a lot of blades at an even number, which created a very round bokeh.
most new cine lenes are 11-19, which have fairly round bokeh when shot wide open, but when you stop them down, they produce different shapes.
picrel, the legendary b-speeds
