ˈsklirə noun
( plural scleras -rəz ; or scle·rae -iˌrē, -ˌrī)
Etymology: New Latin, from Greek sklēros hard
: the dense fibrous opaque white outer coat enclosing the eyeball except the part covered by the cornea and being in some cases reinforced with cartilage and sometimes (as in most birds and in the extinct ichthyosaurs) supported in front by a ring of bony plates — see eye illustration