First, you need to hide the existing text "Home".
Then, insert the new name: ex: "smile"
Inser the codes below to Admin Panel> Theme> CSS> Save.
#app > div > div > header > nav > div > a.item.header-home-link.active12 > span > span { display: none !important; }
#app > div > div > header > nav > div > a.item.header-home-link.active12 > span:after { content: 'smile' !important; }