Final answer:
The word 'wee' can mean both something very small and the early hours of the morning. 'Wee hours' specifically refers to the time after midnight and before dawn.
Step-by-step explanation:
The 3-letter word that can refer to something really small or the early hours of the morning is the word 'wee'. In the context of size, 'wee' means very small or tiny. In terms of time, 'wee hours' refers to the early hours of the morning, just after midnight. This term is often used to describe the time period when it is still dark outside and most people are asleep. It is during these wee hours that the world is quiet and still, much like the hushed atmosphere depicted in scenes with frilly awnings and brightly colored barber's poles described in literature where cities await the bustle of life at dawn.