On page 144; ch.12, what device is Hawthome using when he says that "Remorse" dogs Dimmesdale, and his companion "Cowardice" also has him in her grip? What's it mean?

Hydrophobia (fear of or aversion to water).

The quote would be the one the one

Syllable added to a root word to change its meaning : affixan independent word--example run,walk,book : free morphemeaffix that gives grammatical meaning such as tense or number : inflectiona word part that must attach to a word in order to be usable : bound morphemedegree of comparison formed by adding -er or more to an adjective : comparativedegree of comparison formed by adding -est or most to an adjective : superlativeaffix added to the beginning of a word : prefixaffix added to the end of a word : suffixroot word of lovable : lovetwo roots used together to form one word : combining form