“Secret weapon” in Japanese
Short answer
Secret weapon in Japanese is “秘密兵器” (himitsuheiki). Full meaning: secret weapon.
Other ways to say “Secret weapon” in Japanese
隠し球
kakushidama hidden ball trick; ace up one's sleeve, secret weapon
切り札
kirifuda trump, trump card; ace up one's sleeve, secret weapon
切札
kirifuda trump, trump card; ace up one's sleeve, secret weapon
隠し玉
kakushidama hidden ball trick; ace up one's sleeve, secret weapon
隠しだま
kakushidama hidden ball trick; ace up one's sleeve, secret weapon
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