overflow vs geyser

overflow and geyser both are nouns.

Word	Noun	Adjective	Verb	Adverb
overflow	Yes	No	Yes	No
geyser	Yes	No	Yes	No

As verbs, geyser is a hyponym of overflow; that is, geyser is a word with a more specific, narrower meaning than overflow:

overflow (noun)	geyser (noun)
a large flow	a spring that discharges hot water and steam
the occurrence of surplus liquid (as water) exceeding the limit or capacity

overflow (verb)	geyser (verb)
overflow with a certain feeling	to overflow like a geyser
flow or run over (a limit or brim)