擦れ違う usage and etymology?

Question

擦れ違う is one of my new vocabulary words, so I try to understand as much as I can. I looked up a couple of meanings for the word and I found that it is used to describe 1) when two things pass each other (opposite direction?) and 2) When two people have differing opinions.

I think 擦る means to rub or touch very lightly. However, I'm not sure when I can use 擦れ違う. In the first case, can I only use 擦れ違う when two things pass each other in opposite directions? Is that where the 違う part comes from?

I'm also interested in how the second definition / usage came to be. Thanks for the help!

EDIT: My sources for the above definitions were from space alc

The following example gives me trouble when trying to understand the second meaning.

[（人）と意見が擦れ違う]

Answer 1

In its original meaning, 擦れ違う (also written as すれ違う) means to pass each other in opposite directions at such a close distance that they almost touch. I do not think that it is correct to use it when two things are moving in the same direction, although some people may use it in this meaning.

I do not think that 擦れ違う means “two people have different opinions.”

There are two figurative meanings. One is to come close to each other but fail to meet. The Daijirin dictionary shows an example 待ち合わせ時間に遅れて擦れ違う (to fail to meet because of being late to the appointment). The other figurative meaning is for an argument to go crisscross. This meaning is close to what you wrote in the question but not the same because disagreement means that two people are talking about the same point, but going crisscross means that two people are talking about different points.