When looking at the literary terms, or 'register,' in the novel Gullivers Travels by Jonathan Swift, conduct a close reading of the text and sharply observe and note any terms that you feel helped him to communicate new ideas from a different land to people back home, or people who had never travelled abroad. There are too many to list here, but here a few to give you ideas and get you started.
The term 'metropolis' would not have been in common parlance at the time but would have been useful to denote large conurbations such as cities.
The term 'mean time' from astronomy, which is a time based on the movement of the mean imaginary sun proceeding uniformly along the celestial equator and would not have been needed by people living back at home.
The term 'Levant' would also have been uncommon at home and possibly only used by travellers and geographers as it referred to the Eastern Meditteranean.
The terms 'voyage' and 'adventure' were very particular to epic odyssey narratives and Jonathan Swift himself says that it would not be sensible 'to trouble the reader with long descriptions of our adventures.'
The term 'Lingua Franca' also only has use to travel writers and travellers for it would not be necessary in one's native land - it is a patois of various western languages where enough can be understood to get by in most of those countries.