(idiomatic, transitive) To convey some subject matter in simple terms, avoiding technical or academic language, especially in a way that is considered condescending.

Alternative spelling of put-down

Perfected; practiced ease and confidence.

(neurology, chiefly US) A genetic disorder caused by the presence of all or part of a third copy of chromosome 21 (a chromosomal excess), whereby the patients bear a certain resemblance to the Mongoloid race, such as a small head and tilted eyelids, and typically have a delay in cognitive ability and physical growth.

present participle of dumb down

Of or relating to a hierarchical system that progresses from a single, large basic unit to multiple, smaller subunits. / Produced, controlled, or directed by those at the top of the hierarchy.

Used other than figuratively or idiomatically: see let, down. / (transitive) To allow to descend. / (transitive, idiomatic) To disappoint; to betray or fail somebody

(slang, idiomatic, transitive) to produce or perform (something) admirably or forcefully.

(idiomatic, intransitive) To be quiet; to refrain from being noisy. / (transitive) To dismiss from muster, as a ship's company. / (slang, transitive) Of a man, to have penetrative sex with a woman.

(transitive) To treat or polish with sandpaper.