'Angola-related' is formed in English from the proper noun 'Angola' and the adjective 'related' (the past participle of 'relate'). 'Angola' originates from Portuguese 'Angola', which in turn comes from the Kimbundu word 'Ngóla' (a title of a ruler). 'Related' derives from Latin via Old French and Middle English.

'Angola' changed from the Kimbundu word 'Ngóla' to Portuguese 'Angola' and then entered English as 'Angola'. 'Related' changed from Latin 'relatus' (past participle of 'referre') to Old French 'relater', then to Middle English 'relaten'/'relate', producing modern English 'related', and the compound 'Angola-related' was formed in modern English by combining the place-name and 'related'.

Initially, it meant 'having a relation to Angola', and over time it has retained that core meaning as 'relating to or connected with Angola'.