"Donkey years" is an idiom that describes a long period of time that has passed. Instead of using this common phrase, one can use many other synonyms to add variety to writing or speech. Some alternatives for "donkey years" are "ages," "eon(s)," "forever," "a century," "a millennium," "a lifetime," "an eternity," "a stretch," "an aeon," and "a millennium." Each of these synonyms adds a different nuance to the meaning of the phrase "donkey years" and provides an opportunity to make language more descriptive and engaging. Using synonyms allows writers and speakers to avoid repetition and create more engaging content while still conveying the same meaning.