There are several synonyms for the phrase "fox by pretending to be ill." One of the most common is "feigning sickness," which means pretending to be ill or injured in order to avoid certain responsibilities or situations. Another synonym is "playing possum," which refers to the behavior of pretending to be dead or immobile in order to avoid detection or harm. "Simulating illness" is another synonym, which means pretending to be sick or unwell in order to achieve a certain goal or objective, such as manipulating others or gaining sympathy. Other synonyms for "fox by pretending to be ill" include "faking sickness" and "pretending to be unwell".