Answer: tackon

AnswerCrossword Clue
TACKON

Add as an afterthought

TACKON

Add later

TACKON

Add, as a rider

TACKON
Append
TACKON
Add
TACKONAdd, as an extra charge
TACKONAdd, as a rider to bill.
TACKONAdd as a supplement.
TACKONAdd as a rider
TACKONAdd for good measure
TACKONAdd penalty yardage
TACKONAdd at the last moment
TACKONSubjoin