* Infix: This is the most technical term, specifically referring to a morpheme (meaningful unit) inserted within a word.
* Inserted: This is a general term that describes something placed within something else.
* Interpolated: This word suggests that something has been inserted into an existing sequence, often with the intention of changing its meaning or emphasis.
* Embedded: This implies that the inserted element is fully integrated into the surrounding word.
* Interjected: This implies that something has been suddenly inserted, perhaps abruptly or unexpectedly.
The best word to use will depend on the specific situation and the intended meaning.