Sentence:  Clearly the preferred wound, it ranked in seriousness between a <WSD>'buckshee</WSD>' or 'baksheesh', a slight would that merely took a man out of the line for a short time, and a 'N.Z. smack', which meant being invalided back to New Zealand, usually disabled for life. 
Meaning of the word marked with <WSD> tags:  A wound that is relatively minor but sufficient to get a soldier sent away from the front to the hospital.