Regularly going round by foot (3)
I believe the answer is:
oft
'regularly' is the definition.
(often)
'going round by foot' is the wordplay.
'going round' becomes 'o' (round can mean a round object. I am not sure about the 'going' bit.).
'by' says to put letters next to each other.
'foot' becomes 'ft' (abbreviation).
'o'+'ft'='OFT'
Can you help me to learn more?
(Other definitions for oft that I've seen before include "Many a time to the poet." , "Frequently in archaic term" , "(Poetically) frequently" , "time and again in literature" , "Consistently" .)