Yunhee J. answered 08/01/21
Kind, Passionate, and Experienced Korean Language Tutor
눈빛 is formed with 눈(eye) and 빛(light).
A few example words that include "빛" are as below:
햇빛 해 sun + 빛
하늘빛 하늘 sky + 빛
물빛 물 water + 빛
얼굴빛 얼굴 face + 빛
You can translate the above words as sunlight, color of sky, color of water, facial expression but in Korean, they mean slightly more emotional than color itself. (It embraces the feeling of each word. warm, bright, openness, shiny, ...etc depends on what you are talking about.)
빛 means "light", "lighting" but the above compound words convey expanded feeling of certain condition due to the nature.
Now, let's look at 눈빛.
People's eyes express various emotions - happy, affectionate, caring, sad, angry, revengeful, worried, nervous... you name it.
So when you see 눈빛 in a sentence, you have to understand the person's emotion and then translate it accordingly.
그댈 보는 나의 눈빛은... '그대' is a poetic, favorable term referring to 'you' - it probably means 'lovely' 'full of love/affection' kind of warm glance
그의 눈빛은 적개심으로 가득차 있었다. His eyes were glaring with hostility.
눈빛 can be as versatile as human emotion.
By the way, '은' from '눈빛은' is a particle. It has no meaning but only function of 'explanation', 'isolation',...etc