Mesially: at or to the middle.

Mesinfraepisternum: a sclerite formed between propleuron, mesepisternum, mesepimeron and second coxa.

Meso: middle: as prefix, drops the o when stem begins with a vowel.

Mesoblast: the middles germ layer of the embryos: = mesoderm.

Mesoderm:= mesoblast: gives rise to muscular and circulatory systems.

Mesodont::= amphiodont: q.v.

Mesomeros: the 2d to 5th abdominal segments in Lepidoptera.

Meson: the middle plane of the body.

Mesonotum: the primitively upper surface of the 2d or middle thoracic ring.

Mesophragma: an internal prolongation of the metapraescutum, affording attachment to some of the wing muscles.