et‧i‧ol‧o‧gy /ˌiːtiˈɒlədʒi, $ -ˈɑːlə-/ 
 noun [uncountable and countable][
Date: 1500-1600; 
Language: Latin; 
Origin: aetiologia, from Greek aitia 'cause'] 
technical the cause of a disease or the scientific study of this
—etiological /ˌiːtiəˈlɒdʒɪk
əl◂ $ -ˈlɑː-/
 adjective—etiologically /-kli/
 adverb  [TahlilGaran] Dictionary of Contemporary English ▲