Wiktionary
n. 1 (context military navy English) A commissioned officer of the navy whose rank is immediately below that of a lieutenant. 2 # (context UK English) A commissioned officer of the Royal Navy ranking above a midshipman and below a lieutenant. 3 # (context Australia Canada New Zealand English) A commissioned officer of the navy ranking above an acting sub-lieutenant and below a lieutenant.
Wikipedia
Sub-lieutenant is a junior military officer rank.
In many navies, a sub-lieutenant is a naval commissioned or subordinate officer, ranking below a lieutenant. In the Royal Navy (RN) the rank of sub-lieutenant is equivalent to the rank of lieutenant in the British Army and of flying officer in the Royal Air Force (RAF).
In some armies, sub-lieutenant is the lowest officer rank. However, in Brazil, it is the highest non-commissioned rank, and in Spain, it is the second highest non-commissioned rank.
The NATO rank code is OF-1 (senior).
Usage examples of "sub-lieutenant".
Sub-Lieutenant Sainsbury, had inexcusably caroused with a dozen bottles of beer and Hooky Walker and two of his petty-officer shipmates.
As he gripped the sides of his bunk he saw Quinton peering down at him, with another figure, Sub-Lieutenant Southby, hovering in the rectangle of light from the passageway.
While he had been here in this same hospital with the delirious Sub-Lieutenant Napier, some busybody had noticed in his paybook that one of his inoculations was out of date.
And it never occurred to him that Julio might be with Argensola in a music-hall or in a moving-picture show, enjoying the simple and monotonous diversions of a Paris sobered by war, with the homely tastes of a sub-lieutenant whose amorous conquests were no more than the renewal of some old friendships.
But so far, no one had appeared in support of these day-dreams: the only girls he met at home were the approved daughters of his mother's friends, selected, it seemed to him, for their inherent wholesomeness, and his only feminine contact at Liverpool was a Wren in the Pay Office, who was much too interested in her career to spare any attention for a sub-lieutenant, and met his tentative advances with a smile as thin as his single stripe.
Calamities were raining around the family and saddening his relatives, yet not one grazed the intrepid sub-lieutenant who was persisting in his daring deeds with the heroic nerve of a musketeer.