WordNet sense 1 ((law) a right or legal share of something; a financial involvement with something):

stake

WordNet sense 2 ((usually plural) a social group whose members control some field of activity and who have common aims):

interest group

WordNet sense 3 (a sense of concern with and curiosity about someone or something):

involvement

WordNet sense 4 (the power of attracting or holding one's attention (because it is unusual or exciting etc.)):

interestingness

WordNet sense 5 (a reason for wanting something done):

sake, sake

WordNet sense 6 (be of importance or consequence):

matter to

WordNet sense 7 (be on the mind of):

concern, occupy, worry

WordNet sense 8 (a diversion that occupies one's time and thoughts (usually pleasantly)):

pastime, pursuit