I lean toward calling them 'switched-coil' converters because it is more specific and more descriptive (seeing that they contain one or more inductors).
In fact Motorola tries to discourage widespread use of the term switchmode except when referring to their brand of power converters. From the Wikipedia article:
The term switch mode was widely used until Motorola claimed ownership of the trademark SWITCHMODE for products aimed at the switching-mode power supply market and started to enforce their trademark. Switching-mode power supply, switching power supply, and switching regulator refer to this type of power supply.
The wikipedia article says that buck, boost, buck boost... are SMPS but a doctor at my university once told me that they are just DC-DC converters not SMPS, that's why I am asking.
Wikipedia is right as for the literal meaning of the term, the converters are power supplies and they are operating in switched mode. More specifically they may be designated switching voltage regulators. In a narrower sense, the term SMPS is used for mains operated + isolated power supplies.
more interestingly, you cannot convert DC to DC without some element of AC, usually by a switching means ... a fully isolated converter requires complete conversion to AC ( and then back to DC ) whereas, non-isolated, say a buck converter, requires less net AC component as the duty cycle goes to 100% ( or zero % ) and a maximum at 50% duty cycle ...