What is the name for a word or name that is used to replace another that is forbidden?
For example, a king may forbid people from using the previous king's name. People loyal to the old king may name their children some alternate name that secretly refers to the forbidden name. A specific example (I can't find a source, but did read this) is that the name Marion is a stand-in for Charles Edward Stuart (Bonnie Prince Charlie, full name Charles Edward Louis John Casimir Sylvester Severino Maria Stuart).
I am looking for the name of the (single) word that defines the "replacement" word.
Solution 1:
euphemism - the substitution of an agreeable or inoffensive expression for one that may offend or suggest something unpleasant; also : the expression so substituted.
It's more commonly used in contexts where the "offensive" term is so-called because some (or many) other people consider it rude/smutty or sacrilegious. But effectively the word being avoided is taboo, whether that's because of general perception or the edict of an all-powerful ruler.
Solution 2:
There is a word 'hemiteleia'. Before you get too excited it is not even in the Oxford English Dictionary. But it is recorded by the following two authors:
Roberts, Chris (2006). Heavy Words Lightly Thrown: The Reason Behind Rhyme. Thorndike Press. ISBN 0-7862-8517-6. Bryson, Bill (1990). Mother Tongue. Penguin. ISBN 0-14-014305-X.
I know that Cockney Rhyming Slang is not the precise subject under discussion, but in many instances it is designed to replace a word that the speaker wants to avoid. The way it works is that a word like 'stairs' will be replaced with 'apples and pears'. Since 'pears' rhymes with 'stairs' the speaker will drop the pears. They will then refer to 'stairs' as 'apples'.
In the case of the word 'c**t', the rhyming slang is 'Berkeley Hunt'. So anyone wishing to refer to a woman's genitals will just mention 'her berkeley'.
And so as not to appear sexist about this I should perhaps mention 'cobbler's awls', and we (chaps) all know what a kick in the 'cobblers' feels like.
Now apparently this system of subterfuge is referred to as 'hemiteleia'. It, and Rhyming Slang generally, are extensively discussed in a Wiki article: see.
http://en.wikipedia.org/wiki/Rhyming_slang#cite_note-roberts-1