"Is it wool?"
Here's a hint from the Tips&Hints in the ABCs skill: *"The Greek question mark looks just like the English semi-colon ; but when you are on the Greek keyboard you find it on the Q".
"μάλλινος" is the adjective and translates to woolen/wool/woollen/woolly. "μαλλί" is the noun and should have been accepted here since there is no context. I'm adding it now. Thank you.
I thought it could be either μάλλινος, μάλλινη or μάλλινο depending on the gender of the noun. I chose the neuter option, but it was marked wrong. Can't all three be correct?
Yes, and all three are in the database as correct so it should have been accepted. There may have been some other error. If you could get a screenshot it would help a lot. The accepted translation shown above is neuter