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participant

In a sentence
Každý účastník dostal na začiatku programu mapu.
Each participant received a map at the beginning of the programme.
Každý účastník kurzu dostal certifikát.
Every course participant received a certificate.
Účastníci výletu sa zišli pred stanicou.
The trip participants gathered in front of the station.
Organizátori počítajú účastníkov pri vchode.
Organizers count participants at the entrance.
Source
Slovak National Corpus (SNK) ↗English gloss from the frequency publish path. Hand-reviewed example sentences.
Full attribution on References.