Installation 意為 1.「(設備、電腦程式或軟體的) 安裝」，如 The installation of the new air conditioner took only one hour. (安裝新冷氣機只花了一小時的時間) 2.「系統，設備，裝置」，如 The existing installation is very old. (現有系統/設備非常老舊) 3.「軍事設施」，如 This country has no nuclear installations. (這個國家沒有核子設施) 4.「就任，就職；就職典禮」，如 the installation of a new mayor (新市長的就職) 5.「裝置藝術的展覽作品」，如 There will be an installation art exhibit at the art gallery next week. (下週美術館將舉辦裝置藝術展)。
Installment (這是美國和加拿大的拼法，北美以外是拼成 instalment，只有一個 l) 意為「分期付款的一期；(報紙或雜誌上連載文章或故事的) 一集」，如 I paid for the iPhone 6s Plus in 12 monthly installments. (我分 12 個月付款買下這支 iPhone 6s Plus 手機)；We paid for the digital television by/in instalments. (我們以分期付款方式支付這台數位電視的款項 / 我們分期付款購買這台數位電視)；The novel has been serialized in the newspaper in ten installments. (這部小說已在報紙上連載十期)；Most of his novels were published in a newspaper or magazine in monthly or weekly instalments. (他的大多數小說都以每月或每週連載方式刊登在報章雜誌上)。