The Collaborative International Dictionary of English v.0.48:

Sphaerenchyma \Sphae*ren"chy*ma\, n. [NL., fr. Gr. ??? sphere +
   -enchyma as in parenchima.] (Bot.)
   Vegetable tissue composed of thin-walled rounded cells, -- a
   modification of parenchyma.
   [1913 Webster]