Correct spelling for the English word "hardlier" is [hˈɑːdliə], [hˈɑːdliə], [h_ˈɑː_d_l_i__ə] (IPA phonetic alphabet).
The word "hardlier" is formed from the root word "hard" combined with the suffix "-lier".
The origin of "hard" can be traced back to Old English, where it was spelled "heard". It is derived from the Proto-Germanic word "harduz", meaning "hard" or "difficult". "Hard" has retained its original meaning in English throughout history and is generally used to describe something that requires effort or is not easy.
The suffix "-lier" is derived from Middle English and Old French. It is used to form comparative adverbs from adjectives, indicating "in a manner more (adjective)" or "to a greater extent (adjective)". For example, "slowly" is derived from "slow" using the "-lier" suffix to express a comparative adverb.