Joe joins some guests in an old-time dance (5)
I believe the answer is:
gigue
'dance' is the definition.
(I've seen this before)
'joe joins some guests in an old-time' is the wordplay.
'joe' becomes 'GI' (GI Joe).
'joins' means one lot of letters go next to another.
'some guests in an old time' becomes 'gue' (I am not sure about this - if you are sure you should believe this answer much more).
'gi'+'gue'='GIGUE'
Can you help me to learn more?
(Other definitions for gigue that I've seen before include "Dance movement" , "Lively Renaissance dance" , "dance music" , "Lively Renaissance/baroque dance" , "Small symphony orch." .)