special stresses having a quality, character, identity, or use of its own [special ingredients]
especial may add implications of preeminence or preference [a matter of especial importance]
specific implies a quality or character distinguishing a kind or a species [children with specific needs]
particular stresses the distinctness of something as an individual [a ballet step of particular difficulty]
individual implies unequivocal reference to one of a class or group [valued each individual opinion]
Source: Webster's
