The whole world is one's home
To drift about from place to place; to make home out of wherever one is
Neutral
作为一个考古学家,四海为家那是经常的事儿 | Zuòwéi yīgè kǎogǔ xué jiā, sìhǎi wéi jiā nà shì jīngcháng de shì'er
As an archaeologist, making myself at home in various places is commonplace
[Source]
这个乞丐居无定所,四海为家,真是可怜 | Zhège qǐgài jū wú dìng suǒ, sìhǎi wéi jiā, zhēnshi kělián
This beggar is homeless and roams all around. It's very sad.
[Source]
None
None
四海 (sì hǎi) means "the whole world" or "the whole country"
《汉书》(Hàn Shū), a work documenting the history of the Western Han dynasty (西汉, Xī Hàn, 206 BC - 8 AD). It was written by 班固 (Bān Gù), and is generally known in English as the "Book of Han" or the "History of the Former Han."
This chengyu is from a line in the work listed in the "Origin" section above