“The unofficial, yet commonly used, naval term ‘young gentleman’ referred to a commissioned officer-in-training. The appellation encompassed a variety of ratings including the entry-level positions of captain’s servant (before 1794) and 1st-class volunteer (after 1794), as well as the ratings of midshipman and master’s mate,” writes historian S.A. Cavell in her book Midshipmen and Quarterdeck Boys in the British Navy, 1771-1831. She acknowledges that ‘young gentlemen’ were not necessarily gentlemen by birth, or very young (in her doctoral thesis research, candidates ranged in age from seven to fifty-eight), but typically, “the majority of officer candidates were between the ages of thirteen and twenty-two.”
It’s understandable that the short, youthful-looking Second Lieutenant Courtenay of The King’s Own is increasingly annoyed as the captain of an Indian pilot schooner keeps referring to him as a ‘young gentleman.’
"Very glad we agree upon that point, Captain M—— . Young Gentleman," continued he, addressing himself to Courtenay, “you'll oblige me by not coming to an anchor on my hen-coops. If you wish to sit down, you can call for a chair.”
“Rather annoying,” muttered Courtenay, who did not much like being called "young gentleman."
"A chair for the young gentleman," continued the captain of the schooner. "Starboard a little. [...] “You will now have an opportunity of beholding a very uncommon sight, which is the propitiatory dance to Shivu. There is no occasion for hurrying on so fast, young Gentleman,” continued the captain to Courtenay; "they will continue it till midnight.”
“How excessively annoying that 'captain of his own ship’ is," observed Courtenay to Macallan. "'Young gentleman!' As if he could not see my epaulet.”
“And yet there is nothing particularly to be affronted about. You have a very youthful appearance, and surely you are not displeased at being called a gentleman.”
"Why, no; but that is the reason why I am annoyed, because I cannot take it up.”
— Frederick Marryat, The King's Own
image: Two young midshipmen in sight of home, painting by Philip Richard Morris