This is the 447th most frequent Catalan word.
alta
"Alta" in Catalan means "tall" or "high" (feminine form). It can also mean "discharge" (from a hospital or similar context).
In this sentence, 'alta' refers to the act of registering or subscribing to a service or institution.
Maria va donar-se d'alta al gimnàs per començar a fer exercici.
Maria registered at the gym to start exercising.
Here, 'alta' describes something that is of great vertical height; an adjective describing the tower.
L'edifici més alt del poble té una torre molt alta.
The tallest building in the village has a very high tower.
In this context, 'alta' refers to a release or discharge, often used in medical contexts to indicate someone is cleared from treatment or hospitalization.