Why are jodphurs called jodphurs?

They are actually spelled jodhpurs, not jodphurs as commoncly is used. Originally, jodhpurs (as worn in and around the city in India after which they are named) were tight-fitting only from the knee to the ankle and were flared above the knee; modern stretch-fabrics have allowed jodhpurs to be supportive and flexible, which is perfect for riding.