Once again, getting into colloquial terms, especially 'collectors terms' causes certain problems in trying to classify weapons. For example the well worn term 'scimitar' used consistantly in Victorian romanticism has virtually no place in describing any particular weapon, and the term evolved actually from loose transliteration of the term 'shamshir'. I agree that trying to determine which sabre is a shamshir and which is a tulwar or kilij can be maddening.
It seems to me that a shamshir blade is of wide range of curvature from quite shallow to fully parabolic, and I have seen deeply Parabolic Persian blades mounted with the typical Ottoman hilt seen on kilij. I cannot decide whether this should be called an Ottoman shamshir or Persian kilij!
It seems most likely to call it a shamshir in Ottoman mounts.
The Indian tulwars are also frustrating. While typically mounted in what collectors term 'Indo-Persian' hilt, there are examples that seem to come from regions in Sind, that carry a solid steel Persian type 'shamshir' hilt.
Would this be a tulwar or a shamshir? Since the hilt carries distinctive 'tulwar' elements (the langets and the characteristic quillon terminals) it seems it should be classified tulwar with Persian form hilt.
It seems with many hybrid forms it is virtually impossible to escape more detailed wording in classifying them.Often even when new research has revealed a term to be incorrectly used (such as in the case of jemadhar vs. katar) it is difficult to unseat terms that have become imbedded in the long established vocabulary used in discussion (i.e. collectors terms).
Best regards,
Jim