- focus, focal point, nidus - a central point or locus of an infection in an organism; "the focus of infection"
--1 is a kind of point
--1 is a part of focal infection - nidus - a nest in which spiders or insects deposit their eggs
--2 is a kind of nest
--2 has particulars: wasp's nest, wasps' nest, hornet's nest, hornets' nest