Uptight, nursing temperature, oxygen off the scale (6)
I believe the answer is:
atonal
'off the scale' is the definition.
I can't judge whether this definition defines the answer.
'uptight nursing temperature oxygen' is the wordplay.
'uptight' becomes 'anal' (I've seen this in another clue).
'nursing' indicates putting letters inside.
'temperature' becomes 't' (abbreviation).
'oxygen' becomes 'O' (O is the chemical symbol for oxygen).
't'+'o'='to'
'anal' going around 'to' is 'ATONAL'.
Can you help me to learn more?
(Other definitions for atonal that I've seen before include "Not in a key (mus.)" , "(Music) having no established key" , "(Of music) without key" , "Lacking traditional musical tone structure" , "Keyless" .)