All underground synonyms
un·der·ground
U u adjective underground
- imperceivable — That cannot be perceived; imperceptible.
- minority — the smaller part or number; a number, part, or amount forming less than half of the whole.
- hypogean — Existing or growing underground.
- enigmatical — Pertaining to an enigma.
- covert — Covert activities or situations are secret or hidden.
adj underground
- deep — If something is deep, it extends a long way down from the ground or from the top surface of something.
- clandestine — Something that is clandestine is hidden or kept secret, often because it is illegal.
- fathomless — impossible to measure the depth of; bottomless.
- hypogeal — underground; subterranean.
- backdoor — You can use backdoor to describe an action or process if you disapprove of it because you think it has been done in a secret, indirect, or dishonest way.
- hypogeous — underground; subterranean.
- hole-and-corner — secretive; clandestine; furtive: The political situation was full of hole-and-corner intrigue.
- hidden — concealed; obscure; covert: hidden meaning; hidden hostility.
- hermetical — made airtight by fusion or sealing.
- conspiratorial — If someone does something such as speak or smile in a conspiratorial way, they do it in a way that suggests they are sharing a secret with someone.
noun underground
- fifth column — a group of people who act traitorously and subversively out of a secret sympathy with an enemy of their country.
- gray market — a market operating within the law but charging prices substantially below list prices or those fixed by an official agency.
- metro — the underground electric railway of Paris, France, Montreal, Canada, Washington, D.C., and other cities.
- black-market — to black-marketeer.