Shoalest is a word that is rarely used in everyday language. However, it is related to the word shoal which is commonly found in texts related to fishing and marine biology. Synonyms for the word shoal might be more helpful as a better way to express the idea of shoalest. Synonyms for shoal include, but are not limited to, sandbar, reef, rocky area, shallow waters, and ledge. All of these words are used to describe a relatively shallow area of water that can be hazardous to boats and ships, especially in storms or rough waters. When looking for words to replace shoalest, it might be better to use the phrase "most shallow".