A Whiz; an Ace
This page is the CodyCross answer for the clue below from Dogs, Group 1623, Puzzle 1 (Working Dogs).
Question is: A Whiz; an Ace
and the answer is: BRAINIAC
Word Meaning:
BRAINIAC — (slang, sometimes derogatory) A very intelligent and usually studious, erudite person.
Definitions from Wiktionary.