ˈthēkə noun
( plural the·cae -ē(ˌ)sē)
Etymology: New Latin, from Latin, case, cover — more at tick
1. : sac , capsule , spore case : as
a. : the capsule of a moss
b. : the pollen sac of an anther
2. : an enveloping sheath or case: as
a. : the cuticular case of an insect larva
b. : the sheath of dura mater enclosing the spinal cord
c. : the layer of dense stroma surrounding a Graafian follicle
d. : hydrotheca
e. : the calcareous wall of a coral calyculus
f. : the test of a testate protozoan or rotifer
g. : the dorsal cup of the calyx of a crinoid