…or perhaps different similarities….
Literally: big – same – small – different
Alternately: Generally similar. The similarities between things outweigh their differences. Although the things being compared may differ in a number of details, the broad strokes are the same.
Confusingly, this yojijukugo can an also be used to emphasize that while two things may seem the same, focusing on the details will reveal the ways in which they’re different.
Notes: Writing 違 instead of 異, despite their similar meanings and identical on-readings, is an error.
This compound is derived from a passage in the Zhuangzi, a Daoist text written in the 4th or early 3rd century BCE and the source of the famous story in which a man dreams that he is a butterfly (and then, upon waking, wonders whether he isn’t a butterfly now dreaming that he is a man).