This is the 240th most frequent Spanish word.
mientras
"While" or "as long as."
'Mientras' is used to indicate an action that occurs simultaneously with another.
Mientras caminaba, escuchaba música.
While I was walking, I was listening to music.
'Mientras' indicates a period of time during which something takes place.
Lée mientras aún hay luz.
Read while there is still light.
'Mientras' is used to express a condition for the continuation of an action.