Tweeter's rule for articulating sentence (8)
I believe the answer is:
rainbird
'tweeter's' is the definition.
Both the definition and answer are singular nouns.
Maybe you can see a link between them that I can't see?
'rule for articulating sentence' is the wordplay.
'rule' becomes 'r' (legal abbreviation).
'for' means one lot of letters go next to another.
'articulating' becomes 'ain' (I can't justify this - if you can you should give a lot more credence to this answer).
'sentence' becomes 'bird' (slang term for a prison sentence).
'r'+'ain'+'bird'='RAINBIRD'
Can you help me to learn more?
(Another definition for rainbird that I've seen is " Flighty type".)