Small capital and Uppercase

Small capital noun - A character having the form of an upper-case letter but the same height as lower-case letters.

Uppercase and small capital are semantically related. In some cases you can use "Uppercase" instead a noun phrase "Small capital".

Uppercase noun - One of the large alphabetic characters used as the first letter in writing or printing proper names and sometimes for emphasis.

Small capital and uppercase are semantically related. Sometimes you can replace phrase "Small capital" with "Uppercase", this terms are similar.