Interesting vocabulary for the C2 level

trade-off (between something and something) the act of balancing two things that are opposed to each other.E.g. a trade-off between increased production and a reduction in quality. There is a trade-off between the benefits of the drug and the risk of side effects.

punch above your weight

to be or try to be more successful than others in doing something that normally requires more skill, experience, money, etc. than you have. E.g. This player seems to be able to constantly punch above his weight. He punched above his weight as the party’s foreign affairs spokesman.

at somebody’s behest /bɪˈhest/

(old use or formal) because somebody has ordered or requested it. E.g. at the King’s behest/at the behest of the King.

wind somebody /wɪnd/ to make somebody unable to breathe easily for a short time. E.g. He was momentarily winded by the blow to his stomach. 

haggard: /ˈhæɡəd/ looking very tired because of illness, worry or lack of sleep. Drawn. E.g.
He looked pale and haggard. A haggard face.

drawn:
(of a person or their face) looking pale and thin because the person is ill/sick, tired or worried. E.g. She looked very pale and drawn. Jo looked drawn and strained after her long night’s work.

iridescent: /ˌɪrɪˈdesnt/
showing many bright colours that seem to change in different lights. E.g. a bird with iridescent blue feathers. Her latest fashion collection features shimmering iridescent materials. They are often iridescent, giving them a spectacular array of colours.’The iridescent feathers of the peacock fascinated the small children.  Las iridiscentes plumas del pavo real fascinaron a los niños.

blood-curdling: /ˈblʌd kɜːdlɪŋ/
(of a sound or a story) filling you with horror; extremely frightening. Sp. espeluznante. E.g. a blood-curdling scream/story. Janice let out a blood- curdling scream when she saw the ghostly figure.
Donald Trump and Kim Jong-un trade blood-curdling threats against each other's countries.

catfish: to pretend to be somebody else on a social networking website in order to deceive other people. Lure (someone) into a relationship by means of a fictional online persona. E.g. ‘he was being catfished by a cruel prankster’

‘a victim of catfishing’

holler: /ˈhɒlə(r)/ to shout loudly. E.g. holler (at somebody) Don't holler at me! He hollered something I couldn't understand. He was hollering something about seeing a snake.

holler: (N) A loud cry or shout. E.g. He let out a holler as he fell. Give me a holler.
‘the audience responded with whoops and hollers.

whoop: a loud cry expressing joy, excitement, etc. Sp. hurras, vivcas. E.g. whoops of delight