Seudah means a meal, especially a festive one. There is a mitzvah to eat three seudot on Shabbat (Talmud Shabbat 118b), two on Yomtov and to make a seudat mitzvah, a feast around joyful religious acts such as weddings, barmitzvahs, circumcisions, etc. Lubavitch Chasidim have a tradition to hold a seudat Moshiach on the day after Pesach, anticipating the arrival of the Messiah.
Theres a joke going around that the basic structure of most Jewish holidays is they tried to kill us, we won, lets eat. This has a grain of truth to it. As everyone knows, food plays a big part in Judaism. However, the crassness of the description comes from a pornography-of-food TV cooking-show culture that cant conceive of eating as a spiritual act.
How does one raise up the physiological act of eating? One may turn it into an aesthetic experience graced by good taste, refinement, culinary expertise and beautiful table settings the cooking-show model. This, Rabbi Joseph Soloveitchik argues, is not enough to redeem the act of eating. What transforms it into a religious act is infusing it with chesed, generosity and kindness.
The word seudah itself drives from the verb saad meaning to sustain, or support (Genesis 18:5, Psalms 104:5). By inviting guests, bringing in the poor and the lonely, and sharing wisdom as well as food, one turns a meal into a seudah and binds a group of individuals feeding into a community.