From qualify + -er.

• (RP) IPA: /ˈkwɒl.ɪ.faɪ.ə/, enPR: kwŏlʹĭ-fī-ə
• (America) IPA: /ˈkwɑ.lɪ.faɪ.ɚ/, enPR: kwŏʹlĭ-fī-ər
• (Australia) IPA: /ˈkwɔl.ɪ.fɑɪ.ə/, enPR: kwŏlʹĭ-fī-ə

qualifier (plural qualifiers)

1. One who qualifies for something, especially a contestant who qualifies for a stage in a competition.
2. A preliminary stage of a competition.
   • 2011, Phil McNulty, Euro 2012: Montenegro 2-2 England‎:

     But England's final qualifier, played out in the hostile surroundings of Podgorica City Stadium, turned on two incidents that will have cast a cloud over Capello's delight at reaching another major tournament.

3. (grammar) A word or phrase, such as an adjective or adverb, that describes or characterizes another word or phrase, such as a noun or verb; a modifier; that adds or subtracts attributes to another.
4. (computing, programming) A marker that qualifies or modifies another code element.

• (grammar) modifier

• (antonym(s) of “contestant”): eliminee

• German: Qualifikant

• German: Qualifikationsspiel, Qualifikationsrunde

• German: Kennzeichner, nähere Bestimmung, Beifügung, Attribut

• Russian: квалификатор