The word 'forte' in English is a case of double borrowing: two separate adoptions from two different Romance languages that happen to share the same Latin source. The result is a single English spelling with two distinct pronunciations, two distinct meanings, and two distinct histories.
The older borrowing came from French. In the mid-seventeenth century, English adopted French 'fort' (strong) in its feminine form 'forte' to mean 'a person's strong point' or 'special talent.' French 'fort' descends from Latin 'fortis' (strong, powerful, brave), and in fencing, 'forte' referred to the stronger part of a sword blade, near the hilt — as opposed to the 'foible,' the weaker part near the tip. This fencing sense extended metaphorically to mean any area of strength. Since the word arrived through French, its historically appropriate pronunciation is monosyllabic: /fɔːɹt/, rhyming with 'court.'
The younger borrowing came from Italian. In the 1720s, English adopted Italian 'forte' as a musical dynamic marking meaning 'loud' or 'strong,' abbreviated 'f' on scores. Italian 'forte' also descends from Latin 'fortis,' but the pronunciation is disyllabic in Italian: /ˈfɔrte/. In English musical usage, this became /ˈfɔːɹti/.
Over time, the Italian pronunciation bled into the French-derived sense, and most English speakers now pronounce 'forte' as two syllables regardless of meaning. Usage guides have long protested this conflation, insisting that 'cooking is not my forte' should rhyme with 'court,' not 'latte.' But the battle is effectively lost: the two-syllable pronunciation dominates in American and British English alike, and dictionaries now list it as standard.
Latin 'fortis' derives from Proto-Indo-European *bʰerǵʰ- (high, elevated). The semantic path from 'high' to 'strong' is intuitive: what is elevated — a hilltop, a fortification — is a position of strength. The same PIE root traveled through the Germanic branch to produce Old English 'beorg' (hill, mound), modern English 'barrow' (burial mound) and 'borough' (originally a fortified town), and German 'Berg' (mountain) — the same element found in city names like Hamburg, Nuremberg, and Heidelberg.
The Latin family from 'fortis' is extensive. 'Fortitūdō' (strength) gave English 'fortitude.' 'Fortificāre' (to make strong) gave 'fortify' and 'fortification.' 'Fortūna' (chance, luck — originally the strong force that determines fate) gave 'fortune' and 'fortunate.' The compound 'confortāre' (to strengthen greatly) gave Old French 'conforter' and English 'comfort' — originally meaning to strengthen or encourage, not to soothe. 'Effort' comes through French from Latin 'exfortiāre' (to exert strength).
In musical usage, 'forte' exists within a graduated system of dynamics. 'Pianissimo' (pp) is very soft; 'piano' (p) is soft; 'mezzo piano' (mp) is moderately soft; 'mezzo forte' (mf) is moderately loud; 'forte' (f) is loud; 'fortissimo' (ff) is very loud. Composers have occasionally pushed the extremes further — Tchaikovsky wrote 'pppppp' and 'ffff' — but the standard range from pp to ff covers most musical expression. The combination of 'forte' with 'piano' in the name 'pianoforte' (literally 'loud-soft') gave the piano its name, preserving the two Italian musical terms in a permanent compound.
The twin histories of English 'forte' offer a compact illustration of how English, uniquely among European languages, draws simultaneously from French and Italian — two daughters of the same Latin mother — sometimes borrowing the same word twice through different channels.