Here are some possibilities:
* Consonants that occur next to each other: This is a common phenomenon in many languages. For example, in the word "stop," the consonants "s" and "t" are next to each other.
* Consonants that are pronounced together as a single unit: This is sometimes called a "consonant cluster," or "consonant blend." For example, the "bl" in "blue" is often pronounced as a single unit.
* Consonants that are affected by each other's pronunciation: This is called "assimilation," and it can happen in various ways. For example, the "t" in "cat" might become a "k" sound before the "k" in "cake."
To understand what "abutting consonant" means, it's important to consider the context in which the term was used.
If you can provide more information, I might be able to give you a more specific answer.