:reg " and :reg 0
When you use x, you are cutting to the default register.
# To see what in the default register
:reg "
# To see what in the register 0
:reg 0 # yank register
Using reg 0 to paste
# diw(delete inner word) will register in the default register.
# In order to put the yanked word, use `"0P`.
"0P
True delete in vim
# Just to delete, use "_.
# e.g. to delete a word
"_diw