Meaning of the word Anointed What does "anointed" mean? Is there a difference between the Old Testament definition and the New Testament?
There are 2 types of anointing.
According to Bible Study Tools, anointing, in Holy Scripture, is either material (with oil) or spiritual (with the Holy Ghost), and it doesn't seem to be different between the old and new testaments with material anointing, but there are slight differences with the spiritual anointing.
Material Anointing
In an ordinary sense
Anointing the body or head with oil was a common practice with the Jews, as with other Oriental nations. (Deuteronomy 28:40 ; Ruth 3:3 ; Micah 6:15) Anointing the head with oil or ointment seems also to have been a mark of respect sometimes paid by a host to his guests. (Luke 7:46 and Psalms 23:5)
In an official sense
It was a rite of inauguration into each of the three typical offices of the Jewish commonwealth.

Prophets were occasionally anointed to their office, (1 Kings 19:16) and were called messiahs, or anointed. (1 Chronicles 16:22 ; Psalms 105:15)
Priests, at the first institution of the Levitical priesthood, were all anointed to their offices, (Exodus 40:15 ; Numbers 3:3) but afterwards anointing seems to have been specially reserved for the high priest, (Exodus 29:29 ; Leviticus 16:32) so that &quot;the priest that is anointed,&quot; (Leviticus 4:3) is generally thought to mean the high priest.
Anointing was the principal and divinely-appointed ceremony in the inauguration of the Jewish Kings. (1 Samuel 9:16 &amp; 10:1 ; 1 Kings 1:34 &amp; 39 ) The rite was sometimes performed more than once. David was anointed three times.
Inanimate objects also were anointed with oil, in token of their being set apart for religious service. Jacob anointed a pillar at Bethel. (Genesis 31:13 ; Exodus 30:26-28)

In an ecclesiastical sense
Anointing with oil is prescribed by St. James to be used for the recovery of the sick. (James 5:14) Analogous to this is the anointing with oil practiced by the twelve. (Mark 6:13)
Spiritual Anointing
In the Old Testament a Deliverer is promised under the title of Messiah, or Anointed, (Psalms 2:2 ; Daniel 9:25-26 ) and the nature of his anointing is described to be spiritual, with the Holy Ghost. (Isaiah 61:1) In the New Testament Jesus of Nazareth is shown to be the Messiah (Luke 4:18-19), or Christ or Anointed, of the Old Testament, (John 1:41 ; Acts 9:22 ; Acts 17:2-3 ; Acts 18:4 &amp; 28 ) and the historical fact of his being anointed with the Holy Ghost is asserted and recorded. (John 1:32-33 ; Acts 4:27 &amp; 10:38) Christ was anointed as prophet priest and king.
Spiritual anointing with the Holy Ghost is conferred also upon Christians by God. (2 Corinthians 1:21)
&quot;Anointing&quot; expresses the sanctifying influences of the Holy Spirit upon Christians who are priests and kings to God.