flow vs overflow

flow and overflow both are nouns.

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

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

Other hyponyms of flow include release, spill, spillage, flood, outpouring.

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

flow: the motion characteristic of fluids (liquids or gases)
overflow: the occurrence of surplus liquid (as water) exceeding the limit or capacity

flow (noun)	overflow (noun)
the act of flowing or streaming; continuous progression	a large flow
the motion characteristic of fluids (liquids or gases)	the occurrence of surplus liquid (as water) exceeding the limit or capacity
dominant course (suggestive of running water) of successive events or ideas
any uninterrupted stream or discharge
the monthly discharge of blood from the uterus of nonpregnant women from puberty to menopause
something that resembles a flowing stream in moving continuously
the amount of fluid that flows in a given time

flow (verb)	overflow (verb)
undergo menstruation	overflow with a certain feeling
cover or swamp with water	flow or run over (a limit or brim)
fall or flow in a certain way
move along, of liquids
move or progress freely as if in a stream
cause to flow
be abundantly present