n a pipe that has several lateral outlets to or from other pipes
n a lightweight paper used with carbon paper to make multiple copies
n a set of points such as those of a closed surface or an analogue in three or more dimensions
v make multiple copies of
v combine or increase by multiplication
n. 具有多种形式的东西( manifold的名词复数 ); 多支管; 歧管（汽车引擎用于进气或排气）