Quenya 

empollië

adverb. *retrying, redoing, another attempt

The word empollie appeared in the untranslated phrase á rike empollie in rough notes from the 1960s (PE17/167). Christopher Gilson suggested this was likely an early attempt by Tolkien to define the Quenya expression for “try harder”, elsewhere given as ā rike am(a)ríkie which more literally means “try [with] more trying” (PE17/94). The second element of empollië is clearly based on pol- “to be [physically] able to” and Arael suggested its first element might be en- “again”. If so, it may mean something like “✱[with] retrying, redoing”.

Neo-Quenya: I would avoid empollië in the sense “harder” for purposes of Neo-Quenya, using the á ricë amrícië construction instead; see that entry for discussion. However, empollië might be worth retaining in the sense “✱retrying, redoing, another attempt”. I also think it is worth adapting an intensified form of this noun as ᴺQ. ampollië meaning “great effort, struggle”.