Ma'anar ƙamus na kalmar "shekarun kashi" yana nufin girman girma da haɓakar ƙasusuwan mutum, musamman dangane da shekarun da suka gabata. Yawanci ana ƙayyade shi ta hanyar nazarin X-ray na wasu ƙasusuwa a cikin jiki, kamar hannu da ƙasusuwan wuyan hannu, kuma galibi ana amfani da shi azaman alamar girma da haɓaka ga yara. Shekarun kashi na iya ci gaba ko jinkirta idan aka kwatanta da shekarun da mutum ya yi, wanda zai iya yin tasiri ga lafiyarsa da lafiyarsa gaba ɗaya.