This is the 69th most frequent Japanese word.
大会
Tournament; competition; convention.
大会 is used here to refer to a 'sports event' involving competition among participants.
昨日、学校で運動大会が開かれました。
Yesterday, a sports event was held at school.
大会 is used here to refer to a 'music competition,' indicating a formal event involving participants demonstrating musical skills.
年に一度の音楽大会でピアノを演奏します。
I will perform piano at the annual music competition.
大会 is utilized here to refer to a 'gaming tournament,' denoting a competitive event concentrated on video or board games.