centimeter, (kokuji)
糎 is a Japanese-made kanji (kokuji) that specifically means centimeter. It has no other standalone meanings.
糎 is a kokuji created in Japan by combining 米 (meter) with 厘 (rin, a small unit), to represent centimeter. The exact historical development is uncertain beyond this compound origin.
The left side 米 stands for meter, and the right side 厘 suggests a tiny fraction. Together they make a centimeter: a tiny meter.
For センチ, picture a tiny centimeter ruler made of rice (米) that you use to measure a centipede: centi -> センチ.
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centimeter (esp. of cannon caliber, etc.)