What is the longest word in English that has 45 words?

There is no single word in English that is 45 words long. Words in English are generally considered to be made up of individual units of meaning (morphemes) that are combined to create larger words.

However, you can create very long phrases or sentences in English. For example, you could string together a series of 45 words to create a very long phrase, but that would not technically be a single word.