mysterious

/mɪˈstɪəɹi.əs/adjective

Difficult to explain or understand; coming from an unknown source.

Example sentences

“A mysterious package arrived on the doorstep with no return address.”
“The old house had a mysterious past that nobody in the village would discuss.”

Collocates with 'circumstances': people vanish 'under mysterious circumstances'.

Related words

naiveToo trusting and inexperienced, with little understanding of how the world really works.myriadA very large number of things, too many to count.nannyA person employed to look after a family's children.musterTo manage to show or display something, such as a feeling or effort.nascentOnly just starting to exist or develop.mushroomThe soft, fleshy part of a fungus that grows above the ground or on rotting wood, often shaped like a small umbrella.