In line with Sharke's remarks, there are several American commonly used expressions that would be offensive if considered in their original meaning; e.g. calling someone a "jerk".
Your expression of regret and remorse is truly refreshing and should be rewarded by a classic example of Brit-speak/Ameri-speak: So you may well appreciate the expressions of shock and concern on my British friend's faces when I mentioned that when my father was a young man in the 1930s he wore knickers.
For everyone else, I meant these:
but they pictured my father in something like these: