A qualifier is an early round or match in some competitions. The players or teams who are successful are able to continue to the next round or to the main competition.
例句
Last week Wales lost 5-1 to Romania in a World Cup qualifier.在上周的世界杯预选赛中，威尔士队1比5负于罗马尼亚队。
N-COUNT
(语法中)限定词，修饰语
In grammar, a qualifier is a word or group of words that comes after a noun and gives more information about the person or thing that the noun refers to.
英英词典释义
Noun
1. a contestant who meets certain requirements and so qualifies to take part in the next stage of competition;
"the tournament was won by a late qualifier"
2. a content word that qualifies the meaning of a noun or verb