the world > action or operation > behaviour > bad behaviour > discourtesy > treat discourteously [verb (transitive)] > treat with lack of affability > refuse to recognize (2)
colloquial. transitive. To break off acquaintance or connection with (a person); also (as a single act) to affect not to see or know (a person) on…
intransitive. To pretend not to see, to ignore deliberately. Frequently with intensifying adverb, as to look right (or straight) through (a person).