口切り|くちきりkuchikiri[0]heiban (flat)

1. nounstart broaching (a subject); opening remark; start; commencement; beginning
2. nounevent at the start of the tenth month of the lunar calendar
3. nounopening a sealed jar or container

• Synonym最初さいしょNeutralNeutral and the most common everyday choice; it means the very first one and implies neither speaking up first nor unsealing anything.
• Synonym出だしでだしCasualColloquial. Refers to the opening stretch of something, used when judging how well it got going; unlike 「口切り」 it does not specifically mean speaking first.
• Synonym滑り出しすべりだしCasualColloquial. Describes how something goes in its early stages, as in 「好調な滑り出し」; it evaluates the start rather than marking the act of opening a topic.
• Synonym初口しょくちWrittenWritten/formal prose, and very rare; it simply means the very beginning. In everyday speech use 「最初」 or 「始め」 instead.
• SynonymしょっぱなCasualColloquial. Means right at the very start, as in 「初っ端から失敗」; it points to the first moment, not to opening a conversation or a jar.
• RelatedはじめNeutralNeutral and the most general word for a beginning; it carries no sense of speaking up first or breaking a seal, which is what sets 「口切り」 apart.
• Related当初とうしょWrittenWritten/formal prose. Means 'at first, originally', often contrasted with how things later changed; no nuance of broaching a subject.
• Related開始かいしWrittenWritten/formal prose. Used for starting an activity and common in formal contexts, as in 「試合開始」; it names the act of starting, not an opening remark.
• Related開幕かいまくWrittenWritten/formal prose for a play, season or tournament opening, as in 「開幕戦」; 「口切り」 instead stresses speaking first, opening remarks or unsealing.
• Related発足ほっそくWrittenWritten/formal prose for an organization or system formally being launched, as in 「新内閣が発足」; not about opening a topic.
• Related始まりはじまりNeutralNeutral. Points to the moment something begins or its origin; it has no nuance of taking the lead in speaking.
• Related幕開けまくあけNeutralNeutral. Figuratively marks the dawn of a new era or the start of an event with a grand, solemn air; it never means speaking first.
• RelatedスタートCasualColloquial loanword for setting off or getting started, common in daily life; it has nothing to do with broaching a subject or unsealing a jar.
• RelatedキックオフCasualColloquial loanword for the kickoff of a match, also used figuratively for launching a project; leans business.
• Related幕開きまくあきNeutralNeutral. Refers to the curtain rising on a performance or the dawn of an event; synonymous with 「幕開け」 but somewhat less common.
• RelatedとっつきCasualColloquial. The part you tackle first, and by extension the first impression someone gives; unrelated to opening remarks or unsealing.

Everyday 'beginning' is 「始め」 or 「最初」. 「口切り」 is for leading off, opening a topic, or first opening a sealed jar, as in 「口切りに」; for launching a project say 「キックオフ」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. ある話題わだいを話はなし始はじめること。また、最初さいしょに述のべる言葉ことば。
2. 旧暦きゅうれき十じゅう月がつの初はじめに行おこなわれた季節きせつの行事ぎょうじ。
3. 密閉みっぺいされた壺つぼや容器ようきを初はじめて開あけること。