Significance of Pitryatirtha
Pitryatirtha, as explained in Dharmashastra, has two significant meanings. First, it denotes a receptacle dedicated to the Pitris, which is explicitly prohibited from being used for sipping water. Secondly, it refers to the specific area situated below the thumb and forefinger. Both definitions highlight the cultural and spiritual importance attached to this term in the context of rituals and respect for ancestral figures.
The below excerpts are indicatory and do represent direct quotations or translations. It is your responsibility to fact check each reference.
Hindu concept of 'Pitryatirtha'
Pitryatirtha in Hinduism signifies a sacred receptacle for honoring the Pitris, serving as a ritual space, and also designates a specific area on the hand, emphasizing its spiritual significance in connection with ancestral veneration.
From: Manusmriti with the Commentary of Medhatithi
(1) A term for the receptacle dedicated to the Pitris, which is explicitly stated to never be used for sipping water.[1] (2) Pitrya-tirtha refers to the area located below the thumb and forefinger, as discussed in the text.[2]