午, a pictographic character resembling a pestle for grinding rice, now represented by 杵, serves as a phonetic component.
Another version of the origin of 午: a rope used to manage the horse.
In modern Chinese 午 means:
2.the seventh of the twelve Earthly Branches used by the ancients to denote years, months, or days in combination with the ten Heavenly Branches
Characters formed by the phonetic component午
仵 忤 旿 玝 wǔ
许／許 杵 xǔ chǔ
迕 汻 wù hǔ