The most common and most likely answer to this crossword clue is the 6 letter word ZODIAC
I've seen this crossword clue in The Daily Telegraph
Z
O
D
I
A
C
More clues leading to the result ZODIAC
- About twelve, going round?
- Group of houses – about 12, on reflection?
- Signs Cuba’s to help Australia? On the contrary
- Stars here backed rally round in business zone
- A group of twelve houses?
- Houses seen on a cycle round inside of exotic Cadiz
- Circular diagram, old, found in Cadiz, specially designed
- Diagram, old, found in Cadiz in tatters
- House signs
- Heavenly region around stellar twelve rotating
Buddy explains!

The straight part
We know that "A group of twelve houses?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a group of twelve houses? = zodiac.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does ZODIAC mean?
ZODIAC noun- The belt-like region of the celestial sphere approximately eight degrees north and south of the ecliptic which include the apparent path of the sun, moon, and visible planets.
- The twelve equal divisions of the zodiacal region into signs or houses, each named for a prominent constellation in the region.
- The ecliptic: the belt-like region of the celestial sphere corresponding to the apparent path of the sun over the course of a year.
- Any of various astrological systems considered similar to the above.
- A circle decorated with the signs of the zodiac.