From memory, you can have matches by multiple values. For example, the field with values A¶B¶C will show in a portal the related records in another table with A, B, or C in the related field.
So you could have in your phrases table a calculated field that the complements the PhraseField, with all of the spaces substituted with the ¶ character. You may have to substitute some other characters, too.
Then link your WordField to that mirrored, calculated field.
(I hope my memory is correct - the only way I may have it wrong is that it may only work the other way around: A will match to A¶B¶C, but not vice-versa.)
Given your use of a * wildcard in your example, I think you would want "Apple" to match to all of the following:
Apple, Apples, AppleSauce, Crabapple.
If so, your filter expression can be this:
PatternCount ( PortalTable::PhraseField ; LayoutTable::WordField )
PatternCount will return 0 if WordField is not found in PhraseField.
This method only works with FileMaker 11.
Cody - did you mean to use the wildcard character? If you did, you will get the results that PhilModJunk explains - ie: the pattern of letters could be buried inside a longer word.