Herb loves containing misplaced anger (7)
I believe the answer is:
oregano
'herb' is the definition.
(I know that oregano is a type of herb)
'loves containing misplaced anger' is the wordplay.
'loves' becomes 'oo' (two O's - 'love' means zero in tennis).
'containing' means one lot of letters goes inside another.
'misplaced' indicates anagramming the letters (letters in the wrong places).
'anger' with letters rearranged gives 'regan'.
'oo' placed around 'regan' is 'OREGANO'.
(Other definitions for oregano that I've seen before include "aromatic plant" , "that's aromatic" , "Herb used in cookery" , "leaves for season" , "Dried marjoram" .)