Salam Hilary,
I smiled when I saw your question, and there's honestly no way to find those lyrics in a dictionary, because they are not from MSA, but mostly from the Palestinian accent ;) This song is from the Palestinian heritage and when sung in weddings, I usually hear it in the peasants accent, which is very beautiful :) In our accents we would say زريف الطول instead of ظريف الطول. Also Palestinian peasants would say وكّف تا كولّك instead of وقف تا قولك.
Now for the title's meaning "ظريف الطول":
ظريف: جميل، جذاب/
Beautiful/ Attractive.
الطول: مقدار ارتفاع الإنسان عن الأرض/
Height.
So ظريف الطول in MSA, or زريف الطول in the spoken Jordanian/ Palestinian/ Syrian accents means: The person with a beautiful height :)
I give Ghadeer a lot of credit for translating it to you because it needs patience and hard work :)