V. S. Apte, The Practical Sanskrit–English Dictionary. Look up any word of the Gita in Devanagari, IAST or Harvard-Kyoto, or browse the headwords letter by letter.
Entry पैत्र
पैत्रpaitraa.(-त्री f.) [पितुरिदम् अण्]
(-त्रीFeminine) पितुरिदम् अण्
Relating to a father or ancestors generally, paternal, ancestral.
Sacred to the Manes.
Derived forms and compounds
-त्रम्
The part of the hand between the forefinger and the thumb. (Also पैत्र्य in this sense.)