focal point vs immersion

focal point and immersion both are nouns.

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

As nouns, immersion is a hypernym of focal point; that is, immersion is a word with a broader meaning than focal point:

Other hypernyms of focal point include absorption, concentration, engrossment.

focal point (noun)	immersion (noun)
the concentration of attention or energy on something	a form of baptism in which part or all of a person's body is submerged
a point of convergence of light (or other radiation) or a point from which it diverges	the act of wetting something by submerging it
a central point or locus of an infection in an organism	complete attention; intense mental effort
	sinking until covered completely with water
	(astronomy) the disappearance of a celestial body prior to an eclipse