Lord met drunk entertaining one veteran (3-5)
I believe the answer is:
old-timer
'veteran' is the definition.
(I've seen this before)
'lord met drunk entertaining one' is the wordplay.
'drunk' indicates an anagram.
'entertaining' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'lord'+'met'='lordmet'
'lordmet' anagrammed gives 'oldtmer'.
'oldtmer' placed around 'i' is 'OLD-TIMER'.
(Other definitions for old-timer that I've seen before include "Veteran, elderly person" , "Man of long experience" , "Male with long experience, maybe a prospector" , "Very long-serving person" .)