How to say "tank" in Japanese

• タンクCommon
  nounA tank that holds liquid — water, fuel, and the like; it also covers a cistern or vat. For a fluid container rather than the military vehicle, this loanword is the word you want.
  ガソリンがなくなったので、予備よびタンクに頼たよった。↗

  I fell back on the reserve tank when the gas ran out.
• 戦車せんしゃCommon
  nounThe military vehicle itself: an armored, tracked fighting machine. Use this for tanks in the armed-forces sense only, never for a container of liquid.
  戦車せんしゃや飛行機ひこうきは軍隊ぐんたいを打ち破うちやぶることはできようが、国民こくみんを征服せいふくすることはできない。↗

  Tanks and planes may defeat the troops but they cannot conquer the people.
• 船ふねJLPT N4approx.Common
  nounReally the word for ships and boats; beyond that it has a marginal sense of a large tub- or trough-like container, so for a fluid tank it is seldom what you want — use タンク.

Choose 「タンク」 for a container of liquid (water, fuel), 戦車 for the armored military vehicle; 船 is really the word for ships and boats, covering large tubs or vats only marginally, so it is rarely the right 'tank'.

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

• タンクtank (of fluid)
• 戦車せんしゃtank (military vehicle)
• 軍車ぐんしゃtank (military vehicle)
• パンツァーarmored vehicle
• 船ふねtank
• 壁役かべやくtank (character that soaks up damage for the rest of the party in an MMORPG)