____ League (3)
'league' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for union that I've seen before include "Organisation of employees formed to bargain with the employer" , "Merger like marriage" , "A joining together as in marriage" , "Togetherness" , "Result of joining" .)
(Other definitions for ivy that I've seen before include "Climbing-plant" , "Girl" , "Girl's name; climber" , "With holly, it's seasonally decorative" , "Clinging, parasitical plant" .)