The English and Japanese usually include 'ideographic'. Is there a 「漢字」 preceding your term?

[Ideographic] Variation Indicator
In some cases you may come across an ideograph that your font or your character set doesn’t support. Unicode provides a way of saying, “I can’t represent it, but it looks like this character.”

The approach requires you to add character U+303E immediately followed by a similar looking character. This is called an ideographic variation indicator. This at least gives the reader a chance to guess at the character that is missing.
http://rishida.net/docs/unicode-tutorial/part2

なお、U+303EにIDEOGRAPHIC VARIATION INDICATOR（直訳すると漢字異体字表示子）という似たような名称で、かつ例示字形が点線で囲まれている（通常は不可視である制御文字などを示す）ものが存在するが、これはこれに続く漢字が異体字であることを示す可視の記号 (下駄記号の異体字版) であり、異体字セレクタではない
http://ja.wikipedia.org/wiki/異体字セレクタ

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Note added at 21 mins (2009-11-22 22:17:15 GMT)
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Hmm... that should probably be 'indication', not 'indicator'.
Although there aren't a lot of googits for 'variation indication', it does appear in this authoritative looking tome:
http://unicode.org/book/ch03.pdf