Definition 9.8.40C92F63F8A00

Definition 9.8.4.0C92F63F8A00 Let $X$ be a complex space. A prime divisor over $X$ is represented by a pair consisting of a smooth model $M\to X$ and an irreducible hypersurface $F\subset M$; two pairs are identified if the strict transforms of their hypersurfaces, in the sense of proposition 9.8.3, agree on a common smooth model. The prime divisor is exceptional if the image of $F$ in $X$ has codimension at least two.