This paper examines how we might conceptualise weirdness (da. mærkelighed) as an aesthetic category of music. I presume aesthetic categories to be reflecting both subjective evaluations of phenomena and universal experiences. By considering the etymology of both the Danish and the English term, I can infer that weirdness is fundamentally an affective response to deviation, although it resists being reduced to either negative or positive emotions. Furthermore, by predominantly employing a psychoanalytic framework, I define the weird as the experience of destabilised perceptual categories. Throughout the analysis, I emphasise the perceptual distinction of human and machine to illustrate the weirdness associated with synthetic humanoid singing – i.e., the voice of the cyborg. I finally conclude that the weird affects us in two ways: 1) through the sensory qualities of experiencing a voice that is almost (but not quite) human; 2) by reminding us about the vague ontological border between human and machine.