man keymaps is the driving document to read. The strings section occurs near the end of that document and is limited to assigning strings (ie, multiple commands) per keystroke to function keys alone. In addition to normal PC function keys (F keys, eg, F1, F2, F3 ... F12), it is possible to give non-keyboard imprinted function keys (F13 ... F2xx) a string value to generate upon pressing.
This was not my intention. Instead I wished to re-assign a specific key, CONTROL-y, to generate the multibyte string, "ESCAPE-_". This is a common unix shell command to retrieve the last word of the previous command and insert it at the cursor position of the line being currently crafted. I got in the habit of using CONTROL-y as I had remapped it using an early version of Reflections software, a unix terminal emulator. Reflections had a neat and easy GUI that allowed you to assign any keyboard key to any arbitrary string, any Windows PC command (like copy or paste), any function (using a built in command language).
I would like any information you have as to what I could do for a similar experience. Whether available as a GUI or using the shell. Frankly, I was surprised Gnome Terminal did not have the ability to remap keys, but then I'm new to Linux. Thanks,