Is it used when lying low? (11)
I believe the answer is:
groundsheet
'low?' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for groundsheet that I've seen before include "protective cover" , "campers need it" , "Waterproof base for tent" , "something for campers" , "What keeps a tent dry" .)