first match; opening game; first round
Refers to the first match or game in a series, tournament, or competition. Often used in sports, games, and battles.
初戦で強豪チームと当たることになった。
We ended up facing a strong team in our first match.
He got off to a great start by winning the opening match with a comeback victory.
彼は初戦から全力で挑んだ。
He gave it his all from the very first game.
強豪チームが初戦で敗れて話題になった。
It became big news when the powerhouse team lost in their first match.
They safely got through the first round and advanced to the next stage.
初戦 refers specifically to the first match in a competitive series, whereas 初回 is a broader term meaning 'the first time/episode/instance' used for many kinds of events, not just contests.
初戦 refers to the first match of a scheduled series or tournament, whereas 初陣 highlights the personal significance of one's very first challenge or battle.
初戦 is the first match of a series or tournament, while 最終戦 is the last one.
Compound of 初 (sho, 'first') and 戦 (sen, 'battle' or 'match'). The reading is on'yomi for both characters.