From BiblePortal Wikipedia

Vine's Expository Dictionary of OT Words [1]

Châsı̂yd ( חָסִיד , Strong'S #2623), “one who is pious, godly.” Psalms contains 25 of the 32 appearances of this word.

Basically, hasid means one who practices hesed (“loving-kindness”), so it is to be translated the “pious” or “godly one.” The word’s first biblical occurrence is in Deut. 33:8 where it represents a human being: “Give to Levi thy Thummim, and thy Urim to thy godly one” (RSV). The word appears in Ps. 32:6: “For this shall every one that is godly pray unto thee in a time when thou mayest be found.…” The word is applied to God in Ps. 145:17: “The Lord is righteous in all his ways, and holy in all his works.”

This noun is derived from the noun châsı̂yd.

Webster's Dictionary [2]

(1): ( a.) Of or pertaining to piety; exhibiting piety; reverential; dutiful; religious; devout; godly.

(2): ( a.) Practiced under the pretext of religion; prompted by mistaken piety; as, pious errors; pious frauds.