Carcajear means "to guffaw" or "to cackle," referring to a loud, hearty, and often unrestrained laugh. It's a more vivid and less common word than simply "reír" (to laugh).
In the song, the narrator is imagining a loved one who is no longer there, hearing them "carcajear" (guffaw) even though they aren't physically present. This specific word choice emphasizes the distinct and memorable sound of their laughter, highlighting the depth of the narrator's longing and the vividness of their memory.
This is a song about grief and the way loss reshapes an ordinary home. The narrator imagines a loved one is still around, hears an echo of their laugh, then is met with the silence of an empty room. Small, everyday objects left behind (a lamp, a half-finished glass of water, a shelf of books) become unbearable because they still carry that person's presence.
The chorus wishes for the impossible: rewinding time to undo a mistake and keep that person close. The title itself, a woman's name that also means "pains" or "sorrows" in Spanish, works as a quiet double meaning running through the whole song.