The word 'superior' is a Latin comparative adjective that English borrowed whole, preserving its inflected form rather than adapting it to English morphology. Latin 'superior' means 'higher' or 'upper' — literally 'more above' — the comparative degree of 'superus' (that which is above), derived from the preposition 'super' (over, above).
Latin 'super' descends from the Proto-Indo-European root *upér, meaning 'over' or 'above.' This root has reflexes in every major branch of the Indo-European family, and its descendants are among the most common words in multiple languages. Greek received 'hyper' (ὑπέρ, over, above), the source of the English prefix 'hyper-' in 'hyperbole,' 'hyperactive,' 'hypertension,' and hundreds more. The Germanic branch received *uber, which became Old English 'ofer' (Modern English 'over') and German 'über.' Sanskrit received 'upari' (above). The correspondence is remarkably regular across branches.
This means that 'superior,' 'over,' 'hyper,' and 'über' are all the same word, separated by thousands of years of sound change and borrowed back into English through different channels. When English speakers use both 'over-' and 'super-' as prefixes — oversight/supervision, overcome/surmount, overlord/superior — they are deploying the same PIE root twice, once through its Germanic inheritance and once through Latin borrowing.
In Latin, the comparative 'superior' and the superlative 'suprēmus' (highest, last — source of English 'supreme') formed a complete gradation: 'superus' (upper), 'superior' (higher), 'suprēmus' (highest). English borrowed all three levels. 'Superb' (from Latin 'superbus,' literally 'above-going,' hence proud, magnificent) belongs to the same family, as does 'superlative' (from 'superlātīvus,' carried above, the highest degree).
The word entered English in the late fourteenth century through Old French, initially in hierarchical and religious contexts. A 'superior' in a monastic order was the head of a religious house — a usage that persists in Catholic institutional language today. The adjective quickly generalized to describe anything of higher rank, quality, or position.
The noun use — 'my superior,' meaning a person of higher rank — became standard in military, ecclesiastical, and corporate hierarchies. Lake Superior, the largest of the Great Lakes, received its name from French explorers who called it 'le lac supérieur' — the upper lake, being the highest and northernmost of the chain.
In modern English, 'superior' carries a complex tonal range. It can be straightforwardly descriptive ('a superior product'), institutionally formal ('report to your superior'), or socially loaded ('a superior attitude'). The last usage — meaning snobbish or condescending — turns the word's spatial metaphor against itself: someone who acts 'superior' is behaving as if they are above others, an attitude that is itself considered a social fault.
The 'super-' prefix has become one of the most productive in English, far exceeding its Latin productivity. 'Superman,' 'supermarket,' 'superhero,' 'supernatural,' 'supercomputer,' 'superfood' — modern English uses 'super-' to intensify almost anything. Colloquially, 'super' stands alone as an adjective or adverb meaning 'excellent' or 'very,' a usage that began in the 1840s.
The Italian descendant 'soprano' (from 'sopra,' above, from Latin 'supra/super') — the highest vocal range — demonstrates the same spatial metaphor applied to music. French 'sovereign' (from Vulgar Latin *superānus, 'one who is above') applies it to political authority. In every case, the logic is the same: what is above is what rules, what excels, what surpasses.
From PIE *upér through Latin 'superior' to its modern uses, the word embodies one of humanity's most persistent metaphors: that quality, power, and value are located above, and to be superior is to occupy that elevated position.