Is there a noun that precisely describes the emotion of missing someone/something?
There is longing, but I don't think that's quite right. You can feel longing for something without missing it. I know this word exists in another language (Hebrew – געגוע), but I'm not sure if there is an equivalent in English.
Best Answer
Besides previously-mentioned pining, yearning, and longing, consider wistfulness, "state or characteristic of being wistful", that is, being "full of yearning or longing". Other nouns include yen, "a strong feeling that you want to do something"; craving, "a strong desire; yearning"; thirst, in its figurative sense "a want and eager desire after anything; a craving or longing"; and nostalgia, in its senses "a longing for home or familiar surroundings" and "a bittersweet yearning for the things of the past".