'noncosmic' is a Modern English formation from the prefix 'non-' (from Latin 'non', meaning 'not') + 'cosmic' (from Greek 'kosmikos' via Latin and French), where 'non-' negates and 'cosmic' relates to the universe.

'cosmic' derives from Greek 'kosmikos' (relating to the order of the universe), passed into Late Latin and Old French and then into Middle English as 'cosmic' or 'cosmical'; 'noncosmic' is a more recent negated compound formed in Modern English by adding 'non-'.

Originally 'cosmic' meant 'of or pertaining to the ordered universe'; 'noncosmic' has the straightforward, modern negational sense 'not relating to the universe' and has not undergone substantial semantic drift.