Mid 19th century; earliest use found in Robert Mayne (1808–1868). From (i) post-classical Latin panspermia or its etymon (ii) ancient Greek πανσπερμίαpanspermia; compare -y.
Definition of panspermy in US English:
panspermy
nounpanˈspəːmi
historical
Panspermia.
Origin
Mid 19th century; earliest use found in Robert Mayne (1808–1868). From (i) post-classical Latin panspermia or its etymon (ii) ancient Greek πανσπερμία panspermia; compare -y.