The definition subtropical is one that many may not be familiar with, but it simply defines areas, regions, or places that sit adjacent to or near tropical regions. In the US, the line distinguishing the subtropical region begins around South Florida.
Don't ask someone who is a native of a subtropical region or who lives there what the definition of subtropical is though because it may sound eerie similar to that of tropical climates. In their defense, that is likely because by definition subtropical areas inherently share many of the same characteristics as tropical climates.
A local of a subtropical area may cite the warm conditions, which is also a similarity shared with tropical regions. Yet, they aren't the same. One example of this is that in the coldest historical seasons, northern sections of subtropical regions are susceptible to frost. In tropical regions, the "f" word is never uttered.
It is also reflected through historical data that the subtropical zones typically have hotter peak seasons, although tropical zones are more temperate year-round. So yes, living in subtropical regions can feel much like living in tropical parts of the world too.
Another similarity that people from subtropical climates share with those that live in tropical regions is the rainy season. Another glaring difference here, however, is that the rainy seasons in the deepest parts of the tropics are called monsoons. These intense downpours are akin to the rainy season on steroids for those that live in subtropical climates.
Another vital aspect of these regions is their location which helps to define what a subtropical climate or region is. The physical and geographical location of the subtropical zone is based on the location of the Tropic of Cancer and the Tropic of Capricorn. To the north and south of these respective Tropics, by definition subtropical zones are situated.
The science of the subtropical definition states that they are a conversion of two different types of systems, extratropical and tropical. That also means that there can be both, warm climate and cold climate subtropical systems.
The area designated as the subtropical zone isn't large, but it doesn't carry several distinct differences. For some, it might be considered all the benefits of living in the tropics without any of the concerns. That, however, is not a technical definition of subtropics.