yoda (https://github.com/Bushmills/yoda) is a Forth, existing for the purpose of experimentation. One field of experiments is: Forward references and resolving on demand, uncommon in Forth. Latter is turned on by default, compiling forward references into words must be enabled prior to use (Enable/disable with "shortcuts" ++f, +f and -f).
Needs bash (because coded as bash script). Enjoy.