The most common and most likely answer to this crossword clue is the 5 letter word ARGUS
A
R
G
U
S
More clues leading to the result ARGUS
- Fought about indeed turning hawk-like
- Guardian contends Egypt's leader must go
- Guardian‘s refined sugar
- Giant proves quarrelsome, sapped of energy
- A real giant for starters, the Guardian …
- Guardian‘s sugar snaps
- Guardian contends leader of Egypt must go
- Debates lacking energy in the Guardian
- Lookout is in disagreement with ecstasy being taken
- Guardian of Io is a right little Augustus
Buddy explains!

The straight part
We know that "giant" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case giant = argus.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 ARGUS mean?
ARGUS noun- A watchful guardian.
- An alert, observant person.
- Either of two species of pheasant of Southeast Asia having large ocellated tails.
- Any of various nymphalid butterflies of the genus Junonia. Also called pansies.