煮る【にる】
to boil, to simmer, to stew, to seethe
煮込む【にこむ】
to boil well, to stew, to simmer (for a long time), to cook (various ingredients) together
煮やす【にやす】
to cook inside
雑煮【ぞうに】
soup containing rice cakes and vegetables (New Year's dish)
煮詰める【につめる】
to boil down, to concentrate (soup, milk, stock, etc.), to reach a conclusion, to conclude a discussion