The term "strong vowel" refers to a vowel sound that is clearly pronounced and does not need any help from other sounds to be heard. Some common synonyms for strong vowels include "long vowel", "heavy vowel", or "stable vowel". These types of vowels are typically found in stressed syllables and are often represented by a single letter, such as "a", "e", "i", "o" or "u". Strong vowels are an important aspect of pronunciation and can greatly affect the meaning of a word, especially in languages like English where pronunciation can be ambiguous. By using synonyms for strong vowels, it can help individuals to better understand and pronounce words correctly.