the amount of fluid that flows in a given time
"The plumber adjusted the valve to increase the water flow so we could fill the bathtub faster."
any uninterrupted stream or discharge
"The old pipe was leaking a steady flow of water onto the kitchen floor."
the monthly discharge of blood from the uterus of nonpregnant women from puberty to menopause
"the women were sickly and subject to excessive menstruation"
"a woman does not take the gout unless her menses be stopped"
"the semen begins to appear in males and to be emitted at the same time of life that the catamenia begin to flow in females"
A movement in people or things with a particular way in large numbers or amounts
"The cattle got stuck deep in the flow after the heavy rains turned the field into a swamp."
A morass or marsh.
In plain English: Flow is when you are so focused on doing something that you lose track of time and don't feel tired.
"The flow of traffic was heavy during the evening rush hour."
Usage: Do not use "flow" to mean a morass or marsh, as that is an archaic definition no longer common in modern English. Instead, use it as a noun to describe the continuous movement of a liquid, gas, or people through a space.
cover or swamp with water
"After days of heavy rain, the river swelled and began to flow over its banks, submerging the nearby fields."
To move as a fluid from one position to another.
"The river's water flowed rapidly over the smooth rocks toward the ocean."
In plain English: To flow means to move smoothly and continuously without stopping or getting stuck.
"The river flows gently through the valley."
Usage: Use flow as a verb to describe liquids or gases moving smoothly and continuously in a stream, such as water flowing down a river. It can also apply metaphorically to any process that proceeds without interruption or obstruction.
The word "flow" comes from Middle English and originally meant to move or pass along. Its modern psychological sense, describing a state of intense focus, was coined by Mihaly Csikszentmihalyi in 1975.