great: large in size, high in degree, or high in rank, depending on what it describes
This is the ordinary word for "great" in Hebrew, and it stretches the way "great" and "big" stretch in English. Its core idea is that something far exceeds the normal measure, and what kind of measure it exceeds is decided by the thing it is attached to. A river or a stone is great in size. A fear, a cry, or a sin is great in degree. A person or a nation is great in standing. A voice is great in volume. The word itself does not change meaning across these; the noun it modifies tells you which scale is in view.
The senses below are these different scales, not different words. Hebrew leans on this one adjective where English reaches for a fistful of options (large, loud, mighty, intense, important, elder). That is why it is worth laying the senses out: a translator must choose, but the Hebrew left them fused.
Two of the senses are worth singling out because English does not reuse "great" for them at all. When the word describes a voice or a sound it means loud, and when it contrasts with the word for "small" applied to people it usually means older or more senior rather than physically big. Both are still the same claim, that this one ranks high on its own scale.
When the word is applied to God, it carries the full weight of every scale at once and becomes a confession rather than a measurement: the great God is the one who outstrips all comparison.