Pictogram (象形) of a shield with feather ornaments. It's possible 干 and 單 are variant forms of the same character in oracle bone script, depicting a bifurcated hunting tool.
Also borrowed phonetically as a simplification of 乾 (dry) and 幹.
Sino-Tibetan. Cognate with 扞 (OC *ɡaːns, “to shield; to protect”), 閈 (OC *ɡaːns, “gate”). Compare Tibetanའགལ('gal, “to go against, to violate, to contradict”), Burmeseကာ(ka, “shield; to shield; to block”).
Xíngtiān yǔ dì zhì cǐ (jī gōng zhī guó) zhēng shén, dì duàn qí shǒu, zàng zhī chángyáng zhī shān. Nǎi yǐ rǔ wéi mù, yǐ qí wéi kǒu, cāo gān qī yǐ wǔ.[Pinyin]
When Xingtian fought with the Supreme Deity there (the land of people with odd/uneven upper-arms), the Supreme Deity decapitated him and buried his head at Changyang Mountain. [But Xingtian's] nipples became his eyes, his belly button became his mouth and the thrusting of his shield and battle-axe became his dance.
For pronunciation and definitions of 干 – see 乾 (“dry; moistureless; waterless; arid; to dry; to exhaust; etc.”). (This character is the simplified and variant form of乾).
Notes:
Simplified Chinese is mainly used in Mainland China, Malaysia, and Singapore.
For pronunciation and definitions of 干 – see 豻 (“a kind of wilddog from northernChina, resembling a fox with a blacksnout; etc.”). (This character is a variant form of豻).
For pronunciation and definitions of 干 – see 贛 (“Gan River; Jiangxi, a province of China.; etc.”). (This character is the second-round simplified form of贛).
Notes:
Simplified Chinese is mainly used in Mainland China, Malaysia, and Singapore.
Lục Văn Pảo, Hoàng Tuấn Nam (2003) Hoàng Triều Ân, editor, Từ điển chữ Nôm Tày [A Dictionary of (chữ) Nôm Tày][1] (in Vietnamese), Hanoi: Nhà xuất bản Khoa học Xã hội