The way dad joins chaps entertained by medical specialist (8)
I believe the answer is:
pavement
'the way' is the definition.
(pavement is a kind of way)
'dad joins chaps entertained by medical specialist' is the wordplay.
'dad' becomes 'pa' (both can mean one's father).
'joins' says to put letters next to each other.
'chaps' becomes 'men' (chap means a man).
'entertained by' indicates putting letters inside (inserted letters are hosted or entertained).
'medical specialist' becomes 'vet' (veterinarian, specialist in animal medicine).
'men' going within 'vet' is 'vement'.
'pa'+'vement'='PAVEMENT'
(Other definitions for pavement that I've seen before include "route for walkers" , "Pedestrians' path" , "Footpath" , "Street walkway" , "Pedestrian space" .)