لَا امْرَأَةٌ وَلَا رَجُلَانِ
Not a woman, nor two men.
Two different misconceptions can be corrected by «rajul jāʾanī»: the hearer may think the visitor was a woman, or may think more than one visitor arrived. The first concerns kind or category, and the second number or singularity.
MisconceptionRelevant contrast
A woman arrivedKind: a man arrived
Two men arrivedNumber: one individual arrived
The two effects can be conceptually distinguished even though the same expression may raise both issues.