This is a question I get asked sometimes, and it's one I've reflected upon frequently, having had extensive hypnosis training as well as years of Vipassana, also known as Mindfulness, and Rinzai Zen practice.
I think the first point to understand is that hypnosis is a state and meditation is a state. It is not the method(s) used to get into that state. There are many degrees within each state, from light to very deep.
Both often, but not always, involve a narrowed focus, such as focusing on breathing or body sensations, as is common in many schools of meditation, or on a spinning spiral or swinging watch, as is common in old school style hypnosis. The result is an overall tuning out or disregarding of anything else, and this generally puts one in a more passive, receptive state of mind. The everyday analytical, busy thinking state of mind is temporarily set aside.
Once this state is reached, you can call it hypnosis if you enter into it with a goal or outcome in mind and use suggestions to support that. Or you can dwell in that state for it’s own sake and call it meditation. The states are quite similar but what you do within that state can differ vastly.
Hypnosis is a powerful word with many connotations that unfortunately can scare some people. So many other terms have evolved over time in order to utilize the power of that state without calling it hypnosis. Guided meditation, creative visualization, guided imagery, yoga nidra are only a few.