Participant adjectives are listed in this post. Each word below can often be found in front of the noun participant in the same sentence. This reference page can help answer the question what are some adjectives commonly used for describing PARTICIPANT.
active, actual, average, different, direct, eager, early
enthusiastic, equal, fellow, female, first, former, frequent
full, human, important, individual, key, leading, major
male, new, next, only, other, particular, passive
potential, prominent, real, regular, reluctant, same, second
significant, single, third, unwilling, willing
Hope this word list had the adjective used with participant you were looking for. Additional describing words / adjectives that describe / adjectives of various nouns can be found in the other pages on this website.