Yes. Most people wake up measurably taller than they were the night before — typically by about half a centimeter to a full centimeter, because the discs in the spine lose fluid under gravity during the day and soak it back up while lying flat overnight.
Your spine is a stack of bones called vertebrae, and between each pair sits a disc with a soft, jelly-like center wrapped in a tougher outer layer. Those discs work as cushions. Through a normal day upright, your body weight presses down on them hour after hour, and they slowly give up some of their water. As each disc gets a little thinner, the whole stack gets a little shorter — and so do you.
At night the pressure comes off. Lying flat unloads the spine, and the discs draw fluid back in and swell toward their full thickness again. By morning the stack is at its tallest. Measure yourself right out of bed and again late in the evening, standing the same way both times, and most people will catch a small but real difference.
No — and that distinction matters. Your bones are not growing and shrinking every 24 hours. This is a fluid cycle inside the discs, closer to a sponge being squeezed and then left to refill than to a child getting taller. The effect also tends to get smaller with age, because older discs hold less water to begin with, which is one reason people gradually lose a little height over the years.
See the short version: "You're Taller in the Morning — Things You Didn't Know" on LOE PRESSURE (Science #31).
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Sources: Cleveland Clinic spine-health references; published spine research on diurnal changes in intervertebral disc height and hydration.