The word "惟有" is formed by combining the character 惟, which functions as an adverb meaning "only" or "solely", with the character 有, meaning "to have" or "there is". Together, they create a compound that expresses exclusivity or necessity, effectively meaning "only if" or "there is only", where 惟 modifies 有 to limit the scope of existence or possession to a single condition or entity.