How to say "unbeaten" in Japanese

• 常勝じょうしょうCommon
  no-adjective, suru verb, intransitive verbCovers 'unbeaten' in the sense of ever-victorious: a team or competitor that keeps winning. It stresses the continuing run of victories, and is common in sports talk about sides that never lose.
• 負け知らずまけしらず
  no-adjectiveAlso means 'unbeaten', with the nuance of never knowing defeat. A valid choice but the less common of the two, so 常勝 is the word learners will meet more often.

Both describe a person or team that never loses: 常勝 stresses continual, repeated victory, while 「負け知らず」 presents it as never knowing defeat and is the less common word.

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

• 常勝じょうしょうinvincible
• 負け知らずまけしらずunbeatable