My investigations into the meaning of bian 変 in Chinese translations (the earliest example of which dates back to 489), which have parallels in the Indian and Tibetan languages, reveal that it was used to mean “design; figure; mural painting.” The word bian was used also in the meanings of “a figure; statue,” “a relief,” and “a (mural) painting” in the non-translation texts of the pre-Tang periods. In the non-translation texts from the Tang dynasty, the word bian was used to mean “a (mural) painting on a Buddhist theme.”
Bianxiang 変相, meaning the same as bian, came to be used from the 8th century and was probably coined to express the latter more clearly.
The Sanskrit word citra, meaning “an image, painting, relief” as well as “strange, wonderful,” corresponds semantically very well to bian. The Chinese named Indian flamboyant colourfully-painted artwork, which was totally different from their own traditional artwork and, hence, “unusual, strange,” bian.
Bianwen 変文, found also as part of the titles of several Dunhuang manuscripts, means probably “a script for a painting” used by story-telling monks.