a stone, rock

pusong bato
heart of stone

to throw like a stone

Ibato sa ilog ang mansanas.
Throw the apple into the river

batong buhay
living stone (a stone thought to be breathing)

bato sa lansangan
"stone in the street" = useless person

Binato niya ako.
He/She threw a stone at me.

Salawikain tungkol sa bato:
Tagalog proverb related to stones:

Bato-bato sa langit, 'pag tamaan huwag magalit.
If you throw a stone upwards to the sky,
don't get angry when it drops back down and hits you.

A movie came out in the 1970's with the title Batu-Bato sa Langit.
It starred Nora Aunor, Christopher De Leon and Nida Blanca.