Fantastic psychiatrist doesn't get chair so they write letters, furiously (7)
I believe the answer is:
typists
'they write letters furiously' is the definition.
The definition suggests an adverb but the answer is not.
'fantastic psychiatrist doesn't get chair' is the wordplay.
'fantastic' indicates an anagram (a fantastic or improbable ordering of the letters).
'doesn't get' indicates named letters should be taken away.
'psychiatrist' with 'chair' taken away is 'psytist'.
'psytist' is an anagram of 'TYPISTS'.
'so' is the link.
Can you help me to learn more?
(Other definitions for typists that I've seen before include "They operate character printers" , "Keyboard operators" , "short of key players" .)