(physics) the antiparticle of a down quark

(transitive, arithmetic) To round (a number) to the greatest integer that is not greater than it, or to some other lower value, especially a whole number of hundreds, thousands, etc.

(transitive and intransitive) To reduce in volume by boiling. / (intransitive) To become reduced (to the most central elements or ingredients: to the essence, core, or implication for action).

(transitive) To make (something) lower (especially of clothes). / (transitive) To demolish or destroy (a building etc.). / (transitive) To cause to fall to the floor

(nautical) Of a ship: so far distant that only the masts and sails are visible above the horizon.

To attach or secure with pins. / (idiomatic) To identify something (e.g. a decision or plan) clearly or specifically.

(idiomatic) Thoroughly practiced, rehearsed, or understood; mastered.

(mathematics) Of a real number, converted to an integer by having its fractional component removed.

simple past tense and past participle of round down

(transitive, intransitive, idiomatic) To relax; to make quieter or less obtrusive; to make milder. / To moderate or relax; to diminish or weaken the striking characteristics of; to soften.