The spelling of the word "haddest try" can be explained using IPA (International Phonetic Alphabet). The word "haddest" is pronounced as /ˈhæd.ɪst/, which is the superlative form of "had." The sound "d" represents the past tense of the verb. On the other hand, the word "try" is pronounced as /traɪ/. It means to attempt to do something. Together, "haddest try" means the most attempted action in the past. However, it is not commonly used in modern English.
The phrase "haddest try" does not have a specific etymology because it is not a commonly used phrase. "Haddest" is the past tense of the verb "have" and "try" is a noun or a verb that means attempting something, so together they form a phrase that suggests someone attempted or made an effort in the past. However, without any context or additional information, it is difficult to provide a more accurate analysis.