Discussion : C'est un terme forgé (surréaliste) pour désigner certaines silhouettes et leur transparence ou quelque chose comme cela. On le voit ici en anglais : http://latinamericanmasters.com/english/artist_matta_essay.h... Il voulait donner une forme aux grands transparents de Breton, selon l'auteur. On retrouve cette idée dans l'encyclopédie Larousse. En allemand on a vitrine aussi et on connait le suffixe -eur, donc ce n'est pas problématique pour les amateurs d'art.
http://www.andrebreton.fr/fr/item/?GCOI=56600100056390

Pour les anglophones:
après-guerre, introduction dans l'oeuvre de Matta de silhouettes longilignes, des humanoides tubulaires, des totems ... une tentative aussi de donner une forme aux "grands transparents" de Breton et des surréalistes en général. (cf Giacometti etc.)

"... Then came a drastic turn in Matta's work, represented here by Figure Studies, 1946, a change which lost him a large portion of his New York following. Into this seductive, engulfing spaces intruded tubular humanoids in a variety of contorted positions. It was, according to the artist, a heightened awareness of the horrors of the war and the revelations of the Holocaust that prompted the change. "Instead of my personal psychological morphologies I tried to develop a social morphology using totemic images." There are many contemporary sources for these quasi-mechanical creatures with bizarre extrusions from their "heads," including Giacometti's Invisible Object, the plaster of which Matta had just purchased, the elongated spirit beings in Wifredo Lam's Jungle, Hopi Kachinas which he collected, and his 1942 efforts to give visual form to Breton's Great Transparents. The name he coined for them, "vitreur," with its implication of transparency gives particular credence to this last connection..."