24ac LUPULIN fits the definition but is one letter short. LUPULINE is given either as an adjective to the above or as a noun described as an alkaloid extracted from hops as a colourless volatile...
Has anyone else noticed that you get different versions of the entries from members, depending on whether you have logged onto Answerbank directly or via a link from another website? It looks like...
20ac is "Lack of sufficient power" 9 letters and INABILITY fits so far. But for 19dn 4 letters "Mentally or physically tiring", I have ?I?G, the I being the fifth letter of 20ac....