Select the correctly spelt word.

The correctly spelt word is directory.

Explanation:
Let us examine the spelling and meaning of each given option:
1. directory: This spelling is correct. A directory refers to a book, listing, or file system folder used to store categorized information or files.
2. dictionery: This spelling is incorrect. The correct spelling is dictionary (ending with -ary).
3. dispensery: This spelling is incorrect. The correct spelling is dispensary (ending with -ary).
4. machinary: This spelling is incorrect. The correct spelling is machinery (ending with -ery).

Therefore, directory is the only correctly spelt word among the given choices.