Ma'anar ƙamus na kalmar "kashin baya" shine jerin kashin baya da ke fitowa daga kwanyar zuwa ƙashin ƙashin ƙugu, suna goyon bayan firam ɗin jiki da kuma kare kashin baya. A alamance, “kashin baya” kuma na iya komawa ga mafi mahimmanci ko tsakiya na wani abu da ke goyan bayansa ko riƙe shi tare. Hakanan ana iya amfani da shi don bayyana ƙarfin halin mutum, ƙudurinsa, ko jajircewarsa.