Figure Igor had been led astray by the sign (5)
I believe the answer is:
virgo
'sign' is the definition.
(Virgo is an example)
'figure igor had been led astray' is the wordplay.
I cannot quite see how this works, but
an anagram of 'igor' is 'irgo' which is present in the answer.
A single letter 'v' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
'by the' is the link.
Can you help me to learn more?
(Other definitions for virgo that I've seen before include "Sixth sign of zodiac" , "Large constellation between Leo and Libra" , "Star sign" , "Large constellation -- sign of the zodiac" , "Zodiacal sign" .)