I think teacup sounds cute compared to what they call them here lol.
Here in spain when a dog of a certain breed turns out to be smaller than usual,they call it "enano" which means dwarf..to me this sounds like theres something wrong with the poor thing.
I get stopped alot when I walk Lady by people who want to know where they can get a "dwarf yorkie"
We get ALOT of ads where people (even breeders) use this term and Iv never liked it.