focal point vs nidus

focal point and nidus both are nouns.

Word	Noun	Adjective	Verb	Adverb
focal point	Yes	No	No	No
nidus	Yes	No	No	No

As nouns, focal point and nidus are synonyms defined as:

focal point and nidus: a central point or locus of an infection in an organism

Other synonyms of focal point include focus.

focal point (noun)	nidus (noun)
the concentration of attention or energy on something	a nest in which spiders or insects deposit their eggs
a point of convergence of light (or other radiation) or a point from which it diverges	a central point or locus of an infection in an organism
a central point or locus of an infection in an organism