Bend, as light (7)
I believe the answer is:
refract
'bend as light' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for refract that I've seen before include "(Of lens) change direction of (light beam)" , "Bend ray of light as it meets glass or water" , "Change direction of light, eg, in water/glass" , "Change light's direction" .)