high: rising far above the surrounding level, whether in literal height or in standing, and by extension lifted up in pride
At its core this word simply means tall or elevated. It describes mountains, trees, walls, towers, and the gallows Haman built, and it can measure a person's height or the height of an altar. The picture is always the same: something that reaches up well past what is around it.
From that plain picture the word stretches in two natural directions. One is rank: a person or office can be high the way a tower is high, sitting above others in a chain of authority, and a person once exalted can be brought down. The other is attitude. Because pride imagines itself looming over everyone else, Hebrew speaks of haughty eyes, a high heart, and a proud spirit. The eyes are literally lifted; the heart imagines itself raised above its place.
These are not three different words but one word seen from three angles, and the Bible plays on the link constantly. The prophets warn that everything high will be brought low, meaning both the towering cedars and the towering egos. The same height that is admirable in a mountain is dangerous in a person who looks down on others, and Scripture treats the second as a target for humbling.