His daily desk organizing has become ritualistic, with every item needing to be in its exact place.

ritualistic 是由名词 ritual（仪式）加上形容词后缀 -istic 构成的形容词。ritual 指"仪式、惯例"，后缀 -istic 表示"具有...特性的"。ritualistic 意思是"仪式化的、讲究仪式的"，形容像举行仪式一样严格遵循固定程序的行为。