Middle English word alight comes from Old English līhtan, Old English ā-, Old English lihtan

Detailed word origin of alight

Dictionary entry	Language	Definition
līhtan	Old English (ang)
ā-	Old English (ang)
lihtan	Old English (ang)	To descend, light, alight.. To make light or easy, lighten, alleviate, relieve of burden.
ġelīhtan	Old English (ang)
ālīhtan	Old English (ang)
ālīhted	Old English (ang)
alight	Middle English (enm)

Words with the same origin as alight