(obsolete, chemistry) potassium plumbate

(obsolete, inorganic chemistry) potassium chromate

Previously unknown; unprecedented. / Unknown or known to only few people.

A feudal title of the hereditary proprietor of a manor in manorialism; now largely ceremonial.

(physics) The theories of special relativity and general relativity, two theories in physics developed mainly by Albert Einstein at the beginning of the 20th century from which several important results such as the equivalence of matter and energy and the Einstein field equations are derived.

(idiomatic) To be particularly, especially uncannily, observant; a perceived ability to see in all directions at once.

plural of delusion of grandeur

Of a projectile: missing the target. / (idiomatic) (Very) inaccurate.

(usually in the plural) The false belief that one is important or powerful, accompanying certain mental disorders. / (usually in the plural) Conceitedness or overconfidence.

Alternative form of mother-of-pearl