Correct spelling for the English word "yardest" is [jˈɑːdəst], [jˈɑːdəst], [j_ˈɑː_d_ə_s_t] (IPA phonetic alphabet).
There doesn't appear to be a word "yardest" in the English language. It is possible that the word you are referring to is a misspelling or a word from a different language. If you can provide more information or context, I may be able to assist you further.