Populating a listbox or comobox (validation?) with unique values from large range

Hi all,
I'm having difficulty solving this one. Any suggestions would be appreciated.

For each row on Sheet1, I need to gather an array based on a [partial] cell value lookup to a column on Sheet2.

For example, Sheet1!A2 might the value "Cinnamon Applesauce". I'm extracting the first word of this string ("Cinnamon") and I need to pull all values from Sheet2!J:J that include the word "Cinnamon". So, something like {"Cinnamon sugar", "Cinnamon sticks", "Apple Cinnamon"}
It would be nice if I could put these into a validation combobox on Sheet1 (one per row.)

Also, my worksheets are very large, so speed is a concern.

Thanks for your input.