It is a way to call the guide or leader of the umbanda religion. It comes from the Portuguese of Brazil and is translating as "father".
Pai: Measure for the aggregates in the Russian Empire. Also pay.
Pai is incorrectly written, and should be written as PAI. being its meaning: It is the name of a program of the Bogota Health Secretary, called expanded programme on immunizations, PAI, to vaccinate children and older adults.