Hammer thrower dropping round with book for pound (5)
I believe the answer is:
throb
'pound' is the definition.
(I know that throb is a more specific form of the action pound)
'hammer thrower dropping round with book for' is the wordplay.
'hammer thrower' becomes 'Thor' (the Norse god Thor wields a hammer).
'dropping' suggests deleting specific letters.
'round' becomes 'o' (o is a circular letter).
'with' says to put letters next to each other.
'book for' becomes 'ob' (I can't justify this - if you can you should give a lot more credence to this answer).
'thor' with 'o' taken away is 'thr'.
'thr'+'ob'='THROB'
Can you help me to learn more?
(Other definitions for throb that I've seen before include "Broth (anag.)" , "Pound" , "Palpitate, quiver (with emotion)" , "Beat like heart" , "Beat quickly from excitement etc" .)