### Clue: Maybe Leo and Boris, at heart, are men of Roman stamp? (7)
### Answer: SIGNORI 
 ### Explanation: Definition: men of Roman stamp
  SIGN(in astrology, one of which,maybe is "Leo") **plus**(and) ORI(central letters,at heart of "Boris").
Answer:  Plural of the Italian term of address for men, perhaps of Roman type,stamp.