Fishy series of notes? (5)
I believe the answer is:
scale
This might be a double definition.
'fishy series' is the first definition.
'scale' can be an answer for 'series' (I have seen 'Series of notes' mean 'scale' so perhaps 'series' could also mean 'scale'). I'm unsure of the 'fishy' bit.
'notes?' is the second definition.
(musical notes ordered by pitch)
'of' acts as a link.
Can you help me to learn more?
(Other definitions for scale that I've seen before include "Climb; overlapping plate" , "Deposit formed in a kettle or on teeth" , "Doh, re, me etc" , "Relative size (of something)" , "Ratio between size and representation, on map say" .)