The explorers who invaded Mexico in the sixteenth century found, in addition to treasure of silver and gold, a vegetable treasure in the form of a new fruit, unknown in Europe, which the Mexican Indians called tomati.
They thought sufficiently well of this fruit to take samples back to the Old World, and the name they took into the Spanish and Portuguese languages was tomate (three syllables).
On moving north to France the spelling was retained, but the pronunciation was shortened to two syllables, and this was also the spelling and pronunciation first taken into English.
It wasn’t until the mid-eighteenth century that the present spelling first appeared, apparently having been coined in the belief that the word was of Spanish origin, the -o ending being common in Spanish.
At an early date, the tomato was believed to have aphrodisiac qualities, because of the one-time name of love apple for the fruit.