The term "perflation" is not very commonly used in English, and as such, there are not many synonymous words for it. However, some words that could be used in its place that carry a similar meaning include "permeation," "penetration," and "infiltration." These words describe the process of something passing through a substance or material, often air or moisture moving through a membrane or porous material. Other related words might include "diffusion," "osmosis," and "imbibition." While there isn't necessarily a perfect synonym for "perflation," these related words may be useful in describing similar actions or phenomena.