S: (v) melt, disappear, evaporate (become less intense and fade away gradually) "her resistance melted under his charm"; "her hopes evaporated after years of waiting for her fiance"
S: (v) die down (become progressively weaker) "the laughter died down"
S: (v) collapse (lose significance, effectiveness, or value) "The school system is collapsing"; "The stock market collapsed"
S: (v) fade, melt (become less clearly visible or distinguishable; disappear gradually or seemingly) "The scene begins to fade"; "The tree trunks are melting into the forest at dusk"