Big spider scuttled into rubbish, oddly ugly, note (9)
I believe the answer is:
tarantula
'big spider' is the definition.
'tarantula' can be an answer for 'spider' (tarantula is a kind of spider). I'm not certain of the 'big' bit.
'scuttled into rubbish oddly ugly note' is the wordplay.
'scuttled' becomes 'ran'.
'into' means one lot of letters goes inside another.
'rubbish' becomes 'tat' (low-quality items or material).
'oddly' indicates alternate letters (letters in the odd-numbered positions are used).
'note' becomes 'a' (musical note).
The alternate letters of 'ugly' are 'ul'.
'ran' placed within 'tat' is 'tarant'.
'tarant'+'ul'+'a'='TARANTULA'
Can you help me to learn more?
(Other definitions for tarantula that I've seen before include "hairy creature" , "small, venomous creature" , "Creepy-crawly" , "Large venomous spider" , "web developer" .)