Conditionally loads block if the word immediately following CLOAD is not found after a dictionary search.

69 CLOAD SAMS?

The above will load block 69 if the word SAMS? is not found in the dictionary.

Note, this is an immediate word. Not to be used in a colon definition. Typically, this word will only be used inside of a block, outside of a colon definition, to load an extension library if the library is not already loaded.