### Clue: Can count on union backing about tea break (8)
### Answer: NUMERATE 
 ### Explanation: Definition: Can count
  NUM(abbrev. for the "National Union of Miners" in the UK) + **reversal of**(backing) RE(about,with reference to, from the Latin) **anagram of**(break) TEA.
Answer:  Able to understand, and use, the concept of numbers especially in arithmetical operations,can count as in "accountants are required to be numerate at the  least".