What 轱 means
轱 chiefly appears in 轱辘, meaning “wheel” or “to roll.” In Mandarin, it sounds like “goo” with a high, steady tone; Pinyin writes it gū. The spellings 轱轳 and 毂辘 are also recorded for 轱辘.
The earliest known evidence for the character is in Qin-era manuscripts. Older dictionaries record vehicle, mountain-name, and surname senses. Ming-era examples use 轱辘 for getting up quickly; Qing-era 一轱辘 extends that quick-motion sense to an action.
In ordinary Chinese writing, 轱 usually appears in 轱辘 or 车轱辘; alone, it can look like a dictionary lookup.
Alone, 轱 can leave the intended compound unclear.
Combination ideas
2Questions people ask
1Why does 轱 show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type 轱
轱\8F71Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.