Definition of ‘Sound Pressure’ ambiguous

[gregfowlerphd]

There is a minor ambiguity in the definition. In particular, it is syntactically ambiguous between one reading in which the phrase ‘that is a local deviation from the ambient Pressure’ describes the pressure mentioned at the beginning and a second reading in which it describes the sound wave mentioned in the middle. This ambiguity can be resolved in favor of the first reading (which I take to be the intended one) by revising the definition as follows:

A Pressure that is caused by a Sound Wave and is a local deviation from the ambient Pressure.