1. trump card
2. ace up one's sleeve; secret weapon
Wikipedia definition
3. TrumpA trump is a playing card which is elevated above its normal rank in trick-taking games. Typically an entire suit is nominated as a trump suit - these cards then outrank all cards of plain (non-trump) suits. In other contexts, the term trump card can refer to any sort of action, authority, or policy which automatically prevails over all others.
Read “Trump” on English Wikipedia
Read “切り札” on Japanese Wikipedia
Read “Trump” on DBpedia
Other forms
切札 【きりふだ】


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