Isahani yo gusya ibyuma, izwi kandi nk'icyuma cyo gusya ibyuma, ni ubwoko bwibicuruzwa byuma bikoresha ibyuma bisobekeranye kugirango byambukire gutondekanya ahantu runaka no mu tubari dutambitse, kandi bigasudirwa muri gride ya kare hagati.Ikoreshwa cyane cyane mugukora ibifuniko byumwobo, ibyuma byubatswe byubatswe, ibyuma byurwego rwicyuma, nibindi. Utubari dutambitse muri rusange dukozwe mubyuma bya kare.
Ibyuma bifata ibyuma muri rusange bikozwe mubyuma bya karubone kandi bifite ubuso bushyushye cyane, bushobora kwirinda okiside.Irashobora kandi kuba ikozwe mubyuma.Isahani yo gusya ibyuma ifite ibintu nko guhumeka, gucana, gukwirakwiza ubushyuhe, kunyerera, no kwirinda ibisasu.