This is the 4189th most frequent Spanish word.
lengua
"Lengua" means "tongue" or "language" in English.
Here, 'lengua' refers to the concept of a language as a system of communication, specifically Spanish.
La lengua española es muy rica y diversa.
The Spanish language is very rich and diverse.
In this case, 'lengua' refers to the physical organ, the tongue of a cat.
La lengua de un gato es áspera y útil para limpiar.
A cat's tongue is rough and useful for cleaning.
Here, 'lengua' once again refers to the concept of language, used in the sense of studying a foreign language and its cultural context.