The teacher pointed out his mistake in front of the whole class, which humiliated him.

humiliated 是动词 humiliate 的过去分词形式，humiliate 由词根 humili-（来自拉丁语 humilis，意为"低下的"）和后缀 -ate（表示"使..."）组成，意思是"使某人感到羞耻或失去尊严"。在这里 humiliated 表示"使...感到羞辱/难堪"的心理状态。