Dreg (?), n. [Prob. from Icel. dregg; akin to Sw. dragg, cf. Icel. & Sw. draga to draw. Cf. Draw.]
Corrupt or defiling matter contained in a liquid, or precipitated from it; refuse; feculence; lees; grounds; sediment; hence, the vilest and most worthless part of anything; as, the dregs of society.
We, the dregs and rubbish of mankind.
Dryden.
⇒ Used formerly (rarely) in the singular, as by Spenser and Shakespeare, but now chiefly in the plural.
© Webster 1913.