A solid form or state of matter; something with a definite shape as opposed to a liquid or gas (e.g., solid material).
この薬は固形で、噛んで飲むタイプだ。
This medicine is solid; it's the type you chew and swallow.
固形燃料はキャンプでよく使われる。
Solid fuel is often used for camping.
固形石鹸は液体石鹸より保存がしやすい。
Bar (solid) soap is easier to store than liquid soap.