How do I type a Greek delta with a circumflex? I need to create a capital Greek delta with a circumflex on top of it:



How do I do that in Word or any other text editor (on a Mac)?

The file will be mailed to a publisher, so the letter should appear the same on his computer (so the method should use some standard font).

Note: I do not want to create an image!
You can use Character Viewer to add a combining circumflex (U+0302) to your delta.  You may need to experiment with fonts to see what looks best among the ones which are common to most computers.  My TextEdit version with Helvetica below: