Why pointer dereference was once called "decrement"?
OK, I found a lead.  Just needed to know what to search for: https://en.wikipedia.org/wiki/CAR_and_CDR


  The 704 and its successors has a 36-bit word length and a 15-bit address space. These computers had two instruction formats, one of which, the Type A, had a short, 3-bit, operation code prefix and two 15-bit fields separated by a 3-bit tag. The first 15-bit field was the operand address and the second held a decrement or count. The tag specified one of three index registers. Indexing was a subtractive process on the 704, hence the value to be loaded into an index register was called a "decrement".[2]:p. 8 The 704 hardware had special instructions for accessing the address and decrement fields in a word.[2]:p. 26 As a result it was efficient to use those two fields to store within a single word the two pointers needed for a list.[3]:Intro.


Still, this memory model is very foreign to me, so I wouldn't mind if anyone explained how this would work.