What is the ruling on naming a boy "Nayyar," what does it mean, and is it written "نيار" or "نيّار"?

There is no objection to naming a male newborn Ni'yar, with a kasra on the "nun" and a light "ya." Some of the noble Companions were named thus. Ni'yar is the plural of Nar, which means a mark or a sign. The name can also be pronounced with a fatḥa on the "nun" and a shadda on the "ya" (Nayyar), which is the name of the grandfather of one of the great Hadith (definition) scholars. It is recommended to name children with good names whose meaning or pronunciation is not disputed by people, such as Muhammad, Ahmad, and Abdullah.