Concise Bible Dictionary:

These are activities, divine or human, which may proceed from good or evil. We read of “dead works”: acts of mere ceremony, and the religious efforts of the flesh—the flesh profiteth nothing (Heb. 6:1; Heb. 9:14). These stand in contrast to “works of faith,” which are the expression of life by the operation of the Holy Spirit (Heb. 11). The works of the flesh are detailed in Galatians 5:19-21.
Man is justified by faith apart from the “works of the law” (Rom. 3:20; Gal. 2:16), but real faith will produce “good works,” and these can be seen of men, though the faith itself be invisible (James 2:14-26).
The Lord Jesus when on earth declared that His works gave evidence that He was Son of God, and had been sent by the Father, and that the Father was in Him, and He in the Father (John 9:4; John 10:37-38; John 14:11).
When the Jews were persecuting Christ because He had healed a man on the Sabbath day, He said, “My Father worketh hitherto, and I work” (John 5:17). God had rested from His works of creation on the seventh day, but sin had come in, and in the Old Testament allusions are frequent as to the activity of Jehovah for the spiritual blessing of man.
The apostle Paul, in writing to Titus, insists strongly on good works, that Christianity might not be unfruitful.
Everyone will have to give an account of himself to God (Rom. 14:12); and the wicked dead will be raised and judged according to their works (Rev. 20:12-13).

Strong’s Dictionary of Hebrew Words:

from 5647; an act
KJV Usage: