- zoology the abdomen of a spider or other arachnid
C19: from Greek opisthen behind + soma 1
Examples from the Web for opisthosoma
The appendages of the 2nd somite of the opisthosoma absent, rarely minute and bud-like (some Amblypygi), never pectiniform.
No distinct respiratory stigmata behind the sterna of the 1st and 2nd somites of the opisthosoma.
Respiratory organs in the form of tracheal tubes opening by a pair of stigmata in the 2nd and 3rd somites of the opisthosoma.
Intromittent organ of male beneath sternum of the 1st somite of the opisthosoma.