The most common and most likely answer to this crossword clue is the 6 letter word LIZARD
I've seen this crossword clue in The Times
L
I
Z
A
R
D
More clues leading to the result LIZARD
- Point in Cornwall where you’ll see reptile
- Island zoo initially invested in fat reptile
- Disrespectfully, the Queen’s on the side of a road leading to a windswept village
- Cold blooded sort of woman, difficult husband’s out
- Monitor pass after girl
- Reptilian exotic newts exported from Switzerland in error
- Elizabeth has fear, half-dead seeing a reptile
- Disrespectfully, the Queen's on the side of a road leading to a windswept village
- Reptile Liz put next to a road
- Storyteller maintains Zulu finally defeated saurian
Buddy explains!

The straight part
We know that "reptile" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reptile = lizard.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 LIZARD mean?
LIZARD noun- Any reptile of the order Squamata that is not a snake, usually having four legs, external ear openings, movable eyelids and a long slender body and tail.
- (chiefly in attributive use) Lizard skin, the skin of these reptiles.
- An unctuous person.
- A coward.
- (rock paper scissors) A hand forming a "D" shape with the tips of the thumb and index finger touching (a handshape resembling a lizard), that beats paper and Spock and loses to rock and scissors in rock-paper-scissors-lizard-Spock.
- (in compounds) A person who idly spends time in a specified place, especially a promiscuous female.