Translation:The chair is not close to the window.
Vicino / vicina are rather subjective in meaning, and depending on the type of context it could very well imply near or next to. It's similar to how in English, using the word
near can have a variety of subjective meanings depending on the speaker's intentions. For the purposes of translation, it may be advantageous on Duo's lessons at least, to translate vicina as 'near' because 'next to' is more specifically translated as
accanto a. Hope this helps! :)
Pay attention: "vicino" could be a noun, an adjective or an adverb!
If it is a noun (meaning "neighbour") or an adjective (meaning "near, close") it must agree in gender and number with the noun (or the gender and number of the neighbour).
If it is an adverb, instead, it's invariant: "la sedia non è vicino alla finestra" is a grammatically correct sentence in Italian and it has the same meaning.
Ops! "essere vicino a" was a PREPOSITIONAL PHRASE (locuzione preposizionale), Sorry! Like: accanto a, davanti a, dietro a, lontani da etc.
Normally a" prepositional phrase" is invariant! So the correct answer should be "La sedia non è vicinO alla finistra (Edit May 2015)
(old post) "vicino" means "near, nearby, close" and it is an adjective that should agree in gender and number with the noun. e.g. le finestre sono vicine.; Il bar vicino a casa mia. and so on.