How to Use ItadakimasuItadakimasu should be said before you eat. Ideally, everyone is seated at the table and ready to eat when you say it. It's common for a group to say itadakimasu in unison. However, it's just as common for just one person to say it.
You should clasp your hands together (gassho) and bow your head slightly when you say itadakimasu.
MeaningJapan is a Buddhist culture. Itadakimasu is related to Buddhist principles of respecting all living things.
Itadakimasu is meant to thank the animals and plants that gave up their life for the meal. It's also meant to thank all those who played a part in bring the meal to the table — including fisherman, farmers and the chef.
Finishing Your PlateIn Japan, it's considered wasteful not to finish your plate. This is related to the Buddhist philosophy that all life is sacred. In other words, since something gave up its life for your meal — its a shame to waste it (mottainai).
It's considered more wasteful to leave behind meat or fish. Japanese dishes are generally small and few people have problems finishing their plate. If you don't like something you've ordered and can't finish it — you'll be forgiven. Offer it to your dining companions to see if they'll eat it.