Metaphorize
Within the context of Serial Experiments Lain, metaphorize (メタファライズ) is to project a digital incarnation of one's personality into the Wired, or the act of doing so. It is used as both a verb and a noun. Lain is highly admired in the Wired partly because of her ability to metaphorize herself so completely. The word is used several times in the original Japanese dialogue of the anime as well as the English dub, and even flashes across the screen once in Layer 07, misspelled as "metaphorlize." In the English dub and subtitles, it is sometimes mistranslated as "metamorphosis," or some variaton thereof. This might be because "metaphorize" is not a commonly used word in the English language, not even appearing in most dictionaries.
External Links
Deep Researches Lain: This Japanese-language glossary of terms from SEL includes a definition of metaphorize.