#1858 ἑορτάζω heortazo {heh-or-tad'-zo}

 from G1859; TDNT - n/a; v

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

 1) to keep a feast day, celebrate a feast

—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 - keep the feast 1; 1

—Exhaustive Concordance (KJV Translation Frequency & Location)