In a Nutshell: 清澈 (qīngchè) is a sensory and often poetic word for “clear.” It's not the “clear” of understanding (that's
清楚 qingchu), but the “clear” you can see or hear. Think of a pristine mountain stream so transparent you can count the pebbles on the bottom, the innocent and sincere eyes of a child, or a high, pure singing voice. It evokes a feeling of purity, transparency, and serenity.