The word "颗粒" is formed by combining the characters "颗" and "粒", both of which individually denote small, granular objects. "颗" refers to small, roundish items such as seeds or beads, while "粒" signifies tiny particles or grains like those of sand or rice. Together, they create a compound word that reinforces the concept of granules or small particles, used to describe substances with a fine, granular nature.