Bleeding order

Bleeding order is an order of rules such that one rule destroys the input of another rule.

Example
Consider the following two rules proposed by Schane (1968) for French:

(a) a vowel is nasalized before a nasal, and

(b) a nasal is dropped in syllable-final position.

To derive the output [bõ] of bon, rule (a) must be applied before rule (b). If (b) would precede rule (a) it would bleed rule (a): the vowel cannot be nasalized anymore and [bõ] could not be derived.

Link
Utrecht Lexicon of Linguistics