Excessive pace requiring extra energy (5)
I believe the answer is:
steep
'excessive' is the definition.
(steep can mean exceedingly expensive)
'pace requiring extra energy' is the wordplay.
I cannot quite see how this works, but
'energy' could be 'e' (physics symbol as in E=mc2) and 'e' is located in the answer.
'pace' could be 'step' (synonyms) and 'step' is found in the remaining letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for steep that I've seen before include "Almost perpendicular" , "Stiff - thoroughly wet" , "Having a sharp incline" , "pickle" , "Sharply inclined" .)
