Also see definition of "Cushion" in Word Study
Study Dictionary
Cushion
CUSHION [ISBE]
CUSHION - koosh'-un (proskephalaion): In New Testament, only in Mk 4:38 the Revised Version (British and American). The word means literally, a cushion for the head (the King James Version "pillow") but was also used of one for sitting or reclining upon, e.g. of a rower's cushion. The article used with it in this passage suggests that it was one of the customary furnishings of the boat, and it was probably similar to the cushion placed for the comfort of passengers in the stern of modern boats on the Sea of Galilee. "Silken cushions" of Am 3:12 the Revised Version (British and American) is a rendering of the Hebrew demesheq from its supposed connection with damask. These cushions formed the divan, often the only article of furniture in an oriental reception room. "Cushions" occurs further in the somewhat doubtful the Revised Version, margin rendering of Prov 7:16; 31:22.Benjamin Reno Downer
Also see definition of "Cushion" in Word Study