\a voiceless bilabial fricative usually followed by a voiceless (y)ü or ue sound; often read as ˈf(y)ü\
—used to express relief or fatigue
—used to express disgust at or as if at an unpleasant odor
phew. (2008). In Merriam-Webster Online Dictionary.
Retrieved May 15, 2008, from http://www.merriam-webster.com/dictionary/phew