All may cry, endlessly troubled? Hard to keep 'teary' (9)
I believe the answer is:
lachrymal
'teary' is the definition.
(thesaurus)
'all may cry endlessly troubled? hard to keep' is the wordplay.
I cannot quite see how this works, but
an anagram of 'may' is 'yma' which is present in the answer.
'hard' could be 'h' (abbreviation used in pencil classifications) and 'h' is found in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for lachrymal that I've seen before include "Bone" , "Of tears or weeping" , "Weeping, tearful" , "Charm ally with tears" .)