Entomology definition of Chiasma September 7, 2014 Raj Entomology Dictionary 0 Please Like Us!!! DesiGoogly.com > Education News > Entomology Dictionary > Entomology definition of Chiasma Entomology definition of Chiasma: an X-like crossing of nerve fibers. Chiasma Entomology explanationChiasma Entomology meaningEntomology Chiasma definitionReviews & Comments