Food is a vital contributor to our culture, but ironically, it is also the biggest problem in the world.

ironically 是副词，由名词 irony（讽刺）加上形容词后缀 -ic 构成形容词 ironic，再加上副词后缀 -ally 构成。irony 来自希腊语 eironeia，原指"假装无知"，后来发展为"反讽、讽刺"的意思。ironically 表示"具有讽刺意味的是"，用来描述与预期相反或矛盾的情况。