Dance triggers off conveyor of good wishes (9,4)

I believe the answer is:

greetings card

I'm a little stuck... Click here to teach me more about this clue!

'conveyor of good wishes' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'dance triggers off' is the wordplay.
'off' indicates anagramming the letters.
'dance'+'triggers'='dancetriggers'
'dancetriggers' is an anagram of 'GREETINGS CARD'.

Can you help me to learn more?

(Other definitions for greetings card that I've seen before include "Means of salutation" , "Valentine, for instance" , "message of good wishes" , "It's used for wishing well" , "way to convey birthday wishes?" .)

I've seen this clue in The Irish Independent.

Want a hint initially instead of a full solution? Install my app