The Collaborative International Dictionary of English v.0.48:

Peri- \Per"i-\ (p[e^]r"[i^]-). [Gr. peri`, prep.]
   A prefix used to signify around, by, near, over, beyond, or
   to give an intensive sense; as, perimeter, the measure
   around; perigee, point near the earth; periergy, work beyond
   what is needed; perispherical, quite spherical.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Peri \Pe"ri\ (p[=e]"r[i^]), n.; pl. Peris (p[=e]"r[i^]z).
   [Per. per[imac] a female genus, a fairy.] (Persian Myth.)
   An imaginary being, male or female, like an elf or fairy,
   represented as a descendant of fallen angels, excluded from
   paradise till penance is accomplished. --Moore.
   [1913 Webster]

WordNet (r) 3.0 (2006):

peri
    n 1: a beautiful and graceful girl
    2: (Persian folklore) a supernatural being descended from fallen
       angels and excluded from paradise until penance is done