Late 17th century; earliest use found in George Thomson (1619–1677), physician. From post-classical Latin prolongat-, past participial stem of prolongare prolong.
Definition of prolongate in US English:
prolongate
verb
with objectTo prolong, lengthen.
Origin
Late 17th century; earliest use found in George Thomson (1619–1677), physician. From post-classical Latin prolongat-, past participial stem of prolongare prolong.