Redflag

5 clues
Alert
Warning sign
Danger signal
Warning signal
Sign of trouble
Similar answers:
Abhorred
Abjured
Abovebored
Academiccredit
Acamouflagesuit
Accoutred
Accredit
Accreditation
Accredited
Accredits
Acheckeredpast
Acquired
Acquiredtaste
Acred
Adhered
Adheredto
Admired
Adored
Adoredone
Adoredsuperstar