Needs tray to be used when desk-bound (9)
I believe the answer is:
sedentary
'when desk-bound' is the definition.
I can't judge whether this definition defines the answer.
'needs tray to be' is the wordplay.
'to be' indicates anagramming the letters.
'needs'+'tray'='needstray'
'needstray' is an anagram of 'SEDENTARY'.
'used' acts as a link.
Can you help me to learn more?
(Other definitions for sedentary that I've seen before include "not exercising one's talents?" , "Sitting much and taking little exercise" , "Involving little or no energy" , "describing many office jobs?" , "Yes, red ant could be sitting" .)