[1] : The Collaborative International Dictionary of English v.0.48

january \jan"uary\, n. l. januarius, fr. janus an old latin
   deity, the god of the sun and the year, to whom the month of
   january was sacred; cf. janua a door, skr. y=a to go.
   the first month of the year, containing thirty-one days.
   1913 webster

   note: before the adoption of new style, the commencement of
         the year was usually reckoned from march 25.
         1913 webster

[2] : WordNet (r) 2.0

january
     n : the first month of the year; begins 10 days after the winter
         solstice syn: jan
see also:
jan 

January >> J Words
January, definition of term: January
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