This is the 2329th most frequent Japanese word.
ちり
"ちり" (chiri) means "dust" or "small particles."
In this sentence, "ちり" refers to dust or small particles present in the environment.
彼の部屋にはちりが溜まっていた。
Dust had accumulated in his room.
This proverb uses "ちり" metaphorically to represent small, seemingly insignificant things accumulating into something great.
ちりも積もれば山となる。
Even small particles can accumulate to become a mountain.
Here, "ちり" again describes dust or fine sand in a desert context, showcasing its environmental presence.