'sojourner' originates from Old French, specifically the verb 'sojorner' (or 'sojourner'), where the element related to 'jour' referred to 'a day' or 'to spend the day' and the verb meant 'to stay for a time'.

'sojourner' changed from Old French 'sojorner' into Middle English forms such as 'sojournen' and eventually became the modern English noun 'sojourner' (formed from the verb plus agent suffix '-er').

Initially it had the sense 'to spend the day; remain temporarily', and over time this developed into the noun sense 'a person who stays temporarily' which is the current meaning.