the.com/shark tank

means A situation where you must pitch your idea or ask for help in front of powerful people who are more interested in exploiting your weaknesses than helping you succeed.

from 'Shark' has meant a predatory swindler since the 1500s-1600s — someone who circles the desperate and feeds on them, the way loan sharks still do. 'Tank' here is just a big container, as in fish tank. Put them together and you get a literal tank of sharks, the kind aquariums keep — but the phrase 'shark tank' was already swimming in business slang as a metaphor for cutthroat, predatory environments long before the TV show borrowed it as a title, making the metaphor literal: entrepreneurs tossed into a tank with investors circling like sharks.