Where is the palm of one's hand? It's on your 手のhere (てのひら). Right here. I point to my palm, and say "hand here, is where my palm was."
Another noteworthy thing about this kanji is it can be read as たなごころ. You won't see it read this way as often though so we're only teaching you the main reading.
I bought a small, palm-sized electronic dictionary.