The most common and most likely answer to this crossword clue is the 6 letter word DELUDE
I've seen this crossword clue in The Daily Telegraph
D
E
L
U
D
E
More clues leading to the result DELUDE
- Lead up the garden path in Giverny of 8, so to speak
- Cheat American guy, inserting Spanish article
- Stylish man takes in the Spanish fool
- The Spanish hombre’s taken trick
- Lead on diamonds, then duck?
- Fool taking depth for flood’s gallons
- Fool departs for good in flood
- ‘Dandy’ encompassing the Spanish for ‘fool‘
- Fool died before escape
- Do without love and avoid being fool
Buddy explains!

The straight part
We know that "Lead on" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case lead on = delude.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 DELUDE mean?
DELUDE verb- To deceive into believing something which is false; to lead into error; to dupe.
- To frustrate or disappoint.