Oddly spied people up for a drink (7)
I believe the answer is:
sidecar
'a drink' is the definition.
(sidecar is a kind of drink)
'oddly spied people up' is the wordplay.
'oddly' means one should take alternating letters (letters in the odd-numbered positions are used).
'people' becomes 'race' (people can mean a national group or race).
'up' is a reversal indicator (in down clue: letters go upwards).
The alternating letters of 'spied' are 'sid'.
'race' in reverse letter order is 'ecar'.
'sid'+'ecar'='SIDECAR'
'for' is the link.
(Other definitions for sidecar that I've seen before include "Where a passenger may go" , "Cocktail - cedar is (anag)" , "Appendage to motor cycle" , "Attachment to motor cycle" , "that's suitable for a non-driver" .)