To look after one's own interests, especially material ones: “The director was supposed to distribute the money to various charities; instead, he used it to feather his own nest.”
Browse entries near feather one's own nest
feather grass
feather in one's cap
feather in one's cap, a
feather one's nest
feather one's nest (idioms)
feather palm
feather rot
feather star
featherbed
featherbedded