Considering the etymology of units

So I've been cramming in physics problems all last weekend and into this week. When reading in the book about forces the book uses SI metric system, yet the British imperial unit "pound" is actually a measure of force. That's why we can talk about pounds per square inch. (On the flip side, the British unit for mass is a slug.) Of course, when considering the verb, it makes sense that a pound is a force. And yet we use lb to abbreviate pound when neither letter is in the word. That's cause lb is based off of the Roman measuring system when weight was called a librae. And yet a librae or libra was a scale, often symbolizing justice and equality. Etymology and recycling of words is mind blowing.