Lying back, absorbing sun, bare (6)
I believe the answer is:
supine
'lying' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for supine that I've seen before include "Lying face upward" , "Flat on one's back" , "Lethargic" , "Lying on one's back - passive" , "Recumbent" .)