[1] : WordNet (r) 2.0

malachi
     n 1: a hebrew minor prophet of the 5th century bc syn: malachias
     2: an old testament book containing the prophecies of malachi
        syn: malachias, book of malachi
see also:
malachias book of malachi 

[2] : Easton's 1897 Bible Dictionary

malachi
   messenger or angel, the last of the minor prophets, and the
   writer of the last book of the old testament canon mal. 4:4, 5,
   6. nothing is known of him beyond what is contained in his book
   of prophecies. some have supposed that the name is simply a
   title descriptive of his character as a messenger of jehovah,
   and not a proper name. there is reason, however, to conclude
   that malachi was the ordinary name of the prophet.
   
     he was contemporary with nehemiah comp. mal. 2:8 with neh.
   13:15; mal. 2:10-16 with neh. 13:23. no allusion is made to him
   by ezra, and he does not mention the restoration of the temple,
   and hence it is inferred that he prophesied after haggai and
   zechariah, and when the temple services were still in existence
   mal. 1:10; 3:1, 10. it is probable that he delivered his
   prophecies about b.c. 420, after the second return of nehemiah
   from persia neh. 13:6, or possibly before his return.
   

[3] : Hitchcock's Bible Names Dictionary (late 1800's)

malachi, my messenger; my angel

Malachi >> M Words
Malachi, definition of term: Malachi
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