in some sports, for example football (soccer) and ice hockey, a player who is onside is in a position where playing the ball or puck is allowed 未越位；非越位 Oxford Collocations DictionaryOnside is used with these nouns:- kick
Idioms
get/keep somebody onside
- (British English)
to get/keep somebody’s support 得到（或保持）某人的支持 The party needs to keep the major national newspapers onside if it's going to win the next election. 这个政党要想在下次大选中获胜，就需要得到全国各大报纸的继续支持。