Нахлинула translates to "flooded" or "surged," often referring to emotions or sensations that come over someone suddenly and intensely. It's a vivid and less common verb than everyday actions.
In the song, it's used in the line "Впала, нахлинула" (Fell, flooded/surged), describing how a feeling or perhaps the presence of the beloved has powerfully and unexpectedly overwhelmed the singer, making it a very evocative choice.
Jamala and MONATIK's "КЛИЧУ (KLYChU)" is all about that intense, almost unbearable longing for someone when they're not around. The song really gets into how two days without this person feels like an eternity, as Jamala sings, "Два дні без тебе, наче вічність" [Two days without you, like an eternity]. It's that feeling where you just can't get used to being alone, constantly calling out for them, "Чуєш, я кличу тебе" [Do you hear, I'm calling you].
MONATIK joins in, describing how nights that he used to love now feel endless and lonely without this person, making him wonder, "Чим же це заслужив?" [What did I do to deserve this?]. Both artists express this deep need for the other person to just appear, to be there, because being alone is just too much. It's a powerful song about missing someone so much that it hurts, and how their presence is like a burning sun, making everything better.