HEEDLESSNESSES
Scrabble letter values: H4E1E1D2L1E1S1S1N1E1S1S1E1S1 = 18
Definition
HEEDLESSNESSES is the plural of HEEDLESSNESS.
noun HEEDLESSNESS: a lack of attentiveness (as to children or helpless people).
Synonyms of HEEDLESSNESS: inattentiveness