By ill hap is a phrase used to describe an unfortunate or unlucky occurrence. However, there are many synonyms for this phrase that can be used to express the same idea in various ways. These synonyms can include words such as "unintentionally," "accidentally," "mishap," "miscalculated," "misplayed," or even "unfortunate coincidence." Each of these words can convey a unique implication or interpretation of the situation, depending on the context and tone of the sentence. Overall, by ill hap can be replaced with any number of synonyms, depending on the author or speaker's preference for style or vocabulary, with each word contributing to the overall meaning and impact of the sentence.