cephalodium
noun
ceph·a·lo·di·um
ˌsefəˈlōdēəm
plural cephalodia
-ēə
: an irregular internal or external gall-like growth in lichens that differs from an isidium in having an algal component other than that natural to the lichen
Word History
Etymology
New Latin, from Greek kephalōdēs like a head (from kephal- cephal- + -ōdēs -ode) + New Latin -ium