This is light to carry (7)
I believe the answer is:
lantern
'this is light' is the definition.
(I've seen this before)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for lantern that I've seen before include "Transparent case for holding a light" , "Leading light" , "Cased lamp" , "Lamp with protective transparent casing" , "Top of lighthouse" .)