How to say "grenade" in Japanese

• 手投げ弾てなげだんCommon
  nounThe common word for a hand grenade, literally a projectile thrown by hand; this is the default term when you mean the explosive device itself, as in combat or news reporting.
• グレネード
  nounThe loanword from English 'grenade'; it names the same weapon but is less common, so 手投げ弾 stays the usual choice.
• 擲弾てきだん
  nounA military term for a grenade; in everyday use it is seldom the word you want, 手投げ弾 being the common choice.
• 手榴弾しゅりゅうだん
  nounAnother name for the hand grenade, written fully in kanji; it is less common, and 手投げ弾 is the word to reach for first.
  テロリストが手榴弾しゅりゅうだんを投なげる前まえに爆発ばくはつしてしまい、片腕かたうでを吹き飛ふきとばされてしまった。↗

  The grenade blew up before the terrorist could throw it, and his arm was blown off!

Choose 「手投げ弾」, the common word, for the hand-thrown explosive; 「グレネード」 is the English loanword, 手榴弾 a less common synonym, and 擲弾 a military term you will seldom need.

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

• 手投げ弾てなげだんhand grenade
• グレネードgrenade
• 擲弾てきだんgrenade
• 手榴弾しゅりゅうだんhand grenade