A transmitter who met and heard from an earlier generation of leading scholars may be senior in luqiyy (encounters) to another narrator who did not reach those scholars—even if their ages are close.
Example: ʿAbd Allāh attended an earlier authority's final hadith session. Ḥārith began his studies only after that event. ʿAbd Allāh later learns another item from Ḥārith. Despite similar ages, ʿAbd Allāh has seniority in access to earlier teachers.
Luqiyy concerns the historical generation of transmission opportunities, not simply a chance social meeting. It can decisively shape the classification of a relationship.