What does panchrestārius mean in Latin?

panchrestārius, a noun, means “a confectioner”.

What is the genitive of panchrestārius?

The genitive singular is panchrestāriī. panchrestārius is masculine, second declension.

noun · masculinesecond declension

panchrestārius m (genitive panchrestāriī or panchrestārī)

declension
form	singular	plural
nominative	panchrestārius	panchrestāriī
genitive	panchrestāriī panchrestārī	panchrestāriōrum
dative	panchrestāriō	panchrestāriīs
accusative	panchrestārium	panchrestāriōs
ablative	panchrestāriō	panchrestāriīs
vocative	panchrestārie	panchrestāriī

panchrestārĭus, ii, m. panchrestus,

I. a confectioner: coquos, panchrestarios, Arn. 2, 70.

From panchrestus (“good or useful for everything, universal”), from Ancient Greek πάγχρηστος (pánkhrēstos, “good for all work”).