Sexually homologous traits
Your first definition is correct: a homologous trait is one that can be mapped unambiguously between two samples. What establishes the homologous relationship depends, of course, on the trait or feature being mapped.

For example, one way sexually homologous traits can be identified is by tracing the physical development of a male vs. a female organism. If precursor x becomes y in a developed male and z in a developed female, then y and z can be referred to as homologues.