In my dictionary,
both the definitions of "diminutive" and "midget" are "very small".
But how small are they anyway?
Smaller than my palm?
So small that I can't see?
Or just smaller than a certain object's usual size?
Are they equally small?
Can they be used to describe pepole, animals as well as other objects?
very small for a normal item of that type
for instance, a midget aircraft carrier might be 100 yards/meters long
they are adjectives that can be used on anything although they tend to have special meanings when applied to people. If in doubt, just use 'tiny'