Chronic Lymphocytic Leukemia (CLL) wani nau'in ciwon daji ne da ke shafar jini da kasusuwa. Ana siffanta shi da rashin girma da tarin ƙwayoyin lymphocytes waɗanda ba su balaga ba (wani nau'in farin jini) a cikin jini, ƙasusuwa, da tsarin lymphatic. Kalmar “na yau da kullun” tana nufin jinkirin ci gaba da cutar, yayin da “lymphocytic” ke nufin nau’in farin jini da abin ya shafa (lymphocytes). "Leukemia" kalma ce da ake amfani da ita don bayyana ciwon daji da ke shafar kwayoyin halittar jini a cikin kasusuwa.