It’s Monday, for many people in the Western world the beginning of a new week. In many societies, including the Arab world and societies in the Judeo-Christian sphere, a week consists of seven days (and often does not start on Monday but on the respective day of worship). Not so in many African societies. There, cyclical sequences of days often depend(ed) on the network of markets in which villages participate(ed), with a named day for every market. In the Atlantic language Gubёeher, the week has six days, named after spirit shrines that are worshipped on them and the breaks between them (Cobbinah 2013). But of course these time concepts co-exist with those of the Gregorian calendar which reflect the religious practices of Islam and Christianity. While in Gubёeher, the six-day week that captures the local religious calendar co-exists with the Christian seven-day week (with the week days designated with loan words from French), in closely related Gunyaamolo a different picture emerges. In this predominantly Muslim society, week days for the seven-day week in current use are named with loanwords from Arabic. You can see them in this video by the Senegalese linguist Sokhna Bao-Diop.
For the missionaries of the New Tribes Mission who have been active in this area for decades, Arabic-based names for the days of the week didn’t cut it, certainly because of a combination of religious antipathy and an essentialist view of language that is hostile to loanwords. So when I spent time in a Gunyaamolo village to do linguistic research and asked a speaker for the days of the week, he surprised me by saying: “Oh, I don’t know the Gunyaamolo days of the week. But you can find them on a poster in the school where the missionaries have written them down for us.” And here are the fictional Gunyaamolo week days:

Note the additional irony which must have escaped the missionaries’ attention: the word for week, lokuŋo (literally ‘head of the market’), is also a loanword, and from the Mande language Mandinka, which is strongly associated with Islam to boot!