Holiday distress signal (3,3)
I believe this clue is a double definition.
'holiday' is the first definition.
(thesaurus)
'distress signal' is the second definition.
(I've seen this before)
(Other definitions for may day that I've seen before include "International distress signal as from sinking ship" , "Bank holiday - distress signal (3,3;6)" , "SOS" , "Emergency call" , "Radio distress call" .)
This clue is a double definition.
'holiday' is the first definition.
(I've seen this before)
'distress signal' is the second definition.
(Mayday is an example)
(Other definitions for mayday that I've seen before include "I need help" , "Help urgently needed" , "International radio distress signal" , "Bank holiday - distress signal" , "call for help?" .)