This is the 12514th most frequent Spanish word.
meterse
"Meterse" means "to get into" or "to meddle."
Here, 'meterse' is used to describe physically entering into a place, such as a pool.
Me metí en la piscina porque hacía mucho calor.
I got into the pool because it was very hot.
In this context, 'meterse' refers to an action of involving oneself without being invited or welcome in a social situation.
Ella siempre se mete en las conversaciones cuando no la invitan.
She always gets into conversations when she isn't invited.
Here, 'meterse' is used figuratively; it means engaging in or becoming involved in problematic situations.