come up trumps Definition

trump¹
noun

1a. The suit of cards that is declared to be of a higher value than any other suit;

Form: trumps
1b. A card of this suit.

Form: trump card (also)
2. A secret advantage.
3. colloq
A helpful, reliable, fine, etc person.

verb trumped, trumping

1a. To defeat (an ordinary card, a trick with no trumps or an opponent) by playing a trump;
intr
1b. To lay a trump card when an opponent has led with another suit.
2. To win a surprising victory or advantage over (a person, plan, idea, etc).

Idiom: come up trumps (turn up trumps)

To be unexpectedly useful or helpful in difficult circumstances.

To turn out to be better than expected.

Etymology: 16c: a variant of triumph.

Phrasal Verb: trump something up

To invent or make up false evidence, accusations, etc.