Etymologizing Harry Potter Spells and the Wizardry World!

'Expecto Patronum '  Expecto Patronum, the spell that conjured up Harry’s magnificent stag Patronus, roughly translates into ‘I expect (or await) a guardian’ in Latin, which is apt.  Historically, in Ancient Rome, the word ‘patronus’ meant protector, too, but with very different connotations. A patronus in Ancient Rome was someone of a high class who had a ‘patronage’ relationship with a client, who would usually be less rich, or lower class. In turn, the word ’patronage’ most likely came from the term ‘Pater’, which means ‘father’ in Latin.  'Petrificus Totalus ' First, we have ‘Petra’, which is derived from ‘petros’, which means ‘rock’ in Greek.  ‘Ficus’ is a Latin suffix which denotes ‘making’ or ‘doing’ something.  ‘Totalus’ is a loose reworking of ‘totalis’, which, once again, is Latin, meaning ‘total’ or ‘entire’.  So roughly speaking, ‘Petrificus Totalus’ translates to ‘Make rock totally.’ 'Expelliarmus ' ‘Ex’ means ‘out’ and ‘pellere’ means ‘to drive’, which finally formed the word ‘expel’.  Its definition in basic terms means to ‘drive out’. ‘ Armus’, as you may expect, is indeed Latin for a similar sounding part of the body: the arm, or specifically the shoulder joint. In time, the term ‘arm’ took on combat meaning (such as, to ‘arm’ yourself with a wand) with the Latin term ‘arma’, meaning weapon.  Piecing the syllables back together, we have a rough translation of the phrase ‘drive out weapon’ – which is precisely what Expelliarmus does. 'Lumos ' and 'Nox ' Sister spells Lumos and Nox give light and take it away, respectively. Lumos could well come from the 19th-century Latin word ‘lumen’, which simply means ‘light’. Adding the Latin suffix ‘os’ means to ‘have something’: to have light, in this instance.  Nox is Latin for ‘night’, but is also rooted in Greek mythology. ‘Nyx’, closely related to ‘Nox’, is the name for the Greek goddess of night. 'Sectumsempra ' The first half of his self-made curse, ‘sectum’, is Latin for ‘having been cut’: an interesting choice for a man who has the word ‘sever’ in his own name. The second part of the word, however, is fascinating. Because although ‘sempra’ isn’t a Latin word, it is very close to the word ‘semper’, which was known in the Latin phrase ‘semper fidelis’.