The antonyms for the word "makes higher" can be: reduces, lowers, decreases, diminishes, undermines, weakens, falls, drops, declines, and descends. When we use these words, it means that we are talking about decreasing or lowering something, like the height of an object, the level of a liquid, the value of a commodity, or the prestige of a position. For instance, if we say "the temperature drops" or "the price declines," that means that the quantity of those things has decreased. Similarly, if we say "the value of the currency falls" or "the reputation of the company weakens," it implies that they are losing their worth or position.