How to say thank you in Gujarati
આભાર aabhar is the word. The harder part is knowing when to use it. In a Gujarati home, thanking your partner's mother for every serving can land the way it would if you thanked your own mother for passing the salt: polite, and a little cold.
The words
You will also hear plain English thank you constantly, mixed straight into a Gujarati sentence. That is normal speech, not laziness.
When aabhar is right
Leaving after a meal someone cooked all afternoon. A gift. Someone driving across town for you. Anything where an English speaker would write a note.
What families would rather hear
Appreciation beats gratitude. Praise the thing, not the person's effort, and you sound like family instead of a guest.
Replying when someone thanks you
Most often nobody says anything at all, or you get a warm સારું saaru~, meaning fine, good, all right then. It is the all-purpose filler of spoken Gujarati and worth having ready.