Hindi words for family, the full map
Hindi does not have one word for "grandmother" or one word for "aunt". Each relative has a specific name based on which side of the family they are on, whether they are older or younger than the connecting parent, and whether they are the spouse of that person. Learn the map once and you will never have to guess.
Grandparents
Address form: add जी for respect. Dada ji, nani ji.
Parents and their siblings
Your own siblings
In-laws, your partner's side
Address forms that matter
With any elder relative, adding जी is safe and warm: dada ji, mausi ji, chachi ji. You almost never call in-laws directly by their kinship word; most families settle on aunty ji / uncle ji, and some invite you to mummy ji / papa ji. Wait for the invitation.
Bhaiya and didi are also used with unrelated people who look a little older than you: shopkeepers, cab drivers, a friend's older sibling. It is one of the most common everyday politeness moves in Hindi.
Common confusions
Chacha vs mama. Chacha is your father's brother. Mama is your mother's brother. Do not use them interchangeably; the switch is noticeable.
Bhabhi. It is your older brother's wife, not any sister-in-law. Your partner's brother's wife has her own words (jethani / devrani).
Saala. Literally "wife's brother", but it is also a common insult between men. When you are actually addressing your brother-in-law, say his name or use jija / jiju if he is older, or just his name and yaar. Do not casually shout "saala" across a room.
Gujarati parallels
The Gujarati words are close but not identical. See our Gujarati for family guide for dada, dadi, foi (father's sister), masi (mother's sister), and the Gujarati in-law set. Structure is the same; a few of the words differ.