Material form
type: Concept
narrower: Powder

Powder
type: Concept
broader: Sample shape
broader: Sample form
broader: Material form
definition: 1. A solid substance in the form of tiny loose particles; a solid that has been pulverized. (TIB, NCI Thesaurus OBO Edition). 2. A solid substance in the form of tiny loose particles; a solid that has been pulverized. 3. A loose, dry substance that consists of extremely small pieces, usually made by breaking something up and crushing it (Cambridge dictionary).

Sample form
type: Concept
narrower: Powder

Sample shape
type: Concept
narrower: Powder