Wiktionary
knee sock
n. (cx chiefly in the plural English) a sock that reaches almost up to the knee
Usage examples of "knee sock".
Her one knee sock had lost its elasticity and gathered at her ankle.
After the gifts were all opened and we tried on clothes and picked up the heaps of ribbons and papers, my sisters and I each hung up a wool knee sock on the door of the front-hall closet.
The girl twisted her leg, and though it cost her one of her expensive Oxfords and one knee sock, she dragged herself free of its grasp, sobbing.