The family name Pheasey is classified as being of nickname origin.  Surnames which are derived from a nickname are said to constitute one of the widest and most varied class of family names. 

This particular category encompasses many different types of origin.  The  most obvious  are those  names which are based on a physical characteristic or personal attribute of the initial bearer. 

In this particular instance, the  surname Pheasey is derived from the Anglo Norman French word  "enveise, envoise"  meaning  "merry, playful".  This name was latinised as "invesiatus", indicating "one with a cheerful and playful personality".  Variants of the surname Pheasey include Phease, Pheazey, Vaisey, Vaizey, Feesey and Fasey.

One of the earliest references to this name or to a variant is a record of one Robertus Invesiatus who is listed in the Doomsday Book of Essex in 1086.  However, research is of course on going and this name may have been documented even earlier than the date indicated above.  Adam le Veyse is mentioned in the Assize Rolls of Suffolk and John le Vesie is recorded in 1420. 

It is the names introduced to England from France during the Norman Conquest, under William the Conqueror, which are considered the first true fixed and hereditary family names in England.  These Norman knights and lords identified themselves by their estates in the north of France.  By the thirteenth and fourteenth century however, the use of an hereditary family name was becoming more and more established.