Originally recorded as January, Janaway, Jenery, Jennery, Jennardy, in England, Janvier (France) Janer and Jane in Spain, Januario in Portugal, Gennaro and Zannari (Italy) and many others, and recorded throughout Europe, this is a name of truly ancient origins. It has several possible origins and meanings.
The first is that it was given as a baptismal name to somebody born in January. A possibility is that it is a derivative of the personal name Janus, itself a surname. Janus was the god of gateways and doors, and was regarded as having the power to look both ways at the same time!
Finally it may be a localized form of the city of Genoa, and certainly in England people from that famous port were known as Janaways. It is unclear as to when the name was first recorded but William de Janua was recorded in the Subsidy Tax rolls of the county of Kent, England, in the year 1273, whilst John January married Mary Woodhouse on December 16th 1697 at St Mary Woolnoth, in the city of London.