"Not equal to" is a comparison operator used in mathematics and programming for comparing two values. There are several synonyms for this phrase that can be used interchangeably in order to better convey the comparison being made. Some of these synonyms include "not the same as," "unequal to," "distinct from," "different from," "unlike," and "incompatible with." Each of these synonyms indicates that the values being compared are not identical or equal in some way. Choosing the most appropriate synonym for a particular context can enhance clarity and precision in communication.