It is still "hospital" - but when pronouncing the word in Spanish, the "H" is silent.
antes el hospital
Diviértete en el hospital
Ana está en el hospital.
Estoy harto de ser un paciente de hospital
hospital
Hospital
Pudiera ser "descuartizadero" o aun "matadero". There's not a slang word for hospital in Spanish, it's always hospital
"I go to the hospital" is "Voy al hospital". Many times this is translated as "I am going to the hospital", because English speakers are so used to using the progressive tense, but literally it is "I go to the hospital".
It's the same word and meaning "hospital". It's only different in pronunciation.
Hospital
In English, the word "hospital" is neuter and does not have a gender. However, in languages that assign gender to nouns, such as French or Spanish, "hospital" is masculine (le hospital in French, el hospital in Spanish). In those languages, articles and adjectives associated with "hospital" would reflect its masculine form.
trabaja usted/trabajas en un hospital? (formal/informal)