The most common and most likely answer to this crossword clue is the 5 letter word GIANT
G
I
A
N
T
More clues leading to the result GIANT
- Two soldiers, one huge
- Gargantuan Scotsman stuffed into sports car
- Enormous pair of soldiers
- Two soldiers getting monster
- One engaged in good sex? Absolutely great
- Enormous soldiers
- Very large gin, mixed with a tonic to begin with
- Whopping six-footer in US army?
- Good worker tackling tip of iceberg in Titanic
- Huge soldiers
Buddy explains!

The straight part
We know that "big" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case big = giant.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 GIANT mean?
GIANT noun- A mythical human of very great size.
- Specifically, any of the gigantes, the race of giants in the Greek mythology.
- A very tall and large person.
- A tall species of a particular animal or plant.
- A star that is considerably more luminous than a main sequence star of the same temperature (e.g. red giant, blue giant).
- An Ethernet packet that exceeds the medium's maximum packet size of 1,518 bytes.
- A very large organisation.
- A person of extraordinary strength or powers, bodily or intellectual.
- Jotun
- Very large.