Ma'anar ƙamus na kalmar "bell jar" tana nufin gilashi mai siffar kubba ko murfin filastik da aka sanya akan abu don kare shi daga tasirin waje, kamar ƙura ko gurɓatawa, ko haifar da yanayi mara kyau. don gwaje-gwajen kimiyya ko wasu dalilai. Hakanan ana amfani da kalmar a misalta don bayyana yanayin keɓewa ko ware daga waje, galibi ana danganta shi da tabin hankali ko tashin hankali, kamar yadda yake cikin taken littafin Sylvia Plath mai suna "The Bell Jar."