#4520 σαββατισμός sabbatismos {sab-bat-is-mos'}

 from a derivative of G4521; TDNT - 7:34,989; n m

—Greek Word Study (Transliteration-Pronunciation Etymology & Grammar)

 1) a keeping sabbath
 2) the blessed rest from toils and troubles looked for in the
    age to come by the true worshippers of God and true Christians

—Thayer's (New Testament Greek-English Lexicon)

—Strong's (Greek Dictionary of the New Testament)

—NAS Exhaustive Concordance of the Bible with Hebrew-Aramaic and Greek Dictionaries

 AV - rest 1; 1

—Exhaustive Concordance (KJV Translation Frequency & Location)