There is some probability, supported by the mythology and -ss- form, that the name Larissa is Pelasgian — a prehellenic language of Eastern Greece and Western Anatolia dating from the late neolithic to c. 500 BC. Despite this later date nothing but anthroponyms and toponyms are recorded. From the bronze age it is increasingly supplanted by Mycenaean and ancient Greek dialects as the Pelasgians increasingly identify as Archaeans and Hellenes and adopt Hellenic language and culture. It could be related to Minoan or Egyptian, but the Minoan language is still undeciphered (not helped by the proliferation of forgeries).
Larisa can derive as well from Ancient Greek λάριξ (lárix) meaning "larch" or from λάρος (láros) meaning "seagull; cormorant" or λαρός (larós) meaning "sweet; pleasing".
Larisa literally means Laughter in the Spanish language, and a seagull in Greek. It is also the name of a historical city in accent Greece that refers to the word CITADEL (meaning listed below) Later this name was associated with myths and idol worship leaders, then later of a martyr saint. A CITADEL is the core fortified area of a town or city. It may be a fortress, castle, or fortified center. The term is a diminutive of "city" and thus means "little city", so called because it is a smaller part of the city of which it is the defensive core. Citadel /ˈsɪtədəl; -ˌdɛl/ Noun 1. A stronghold within or close to a city 2. Any strongly fortified building or place of safety; refuge 3. A specially strengthened part of the hull of a warship 4. (often capital) the headquarters of the Salvation Army.