Expressed frustration as small, hard blocks carelessly handled (7)
I believe the answer is:
pshawed
'expressed frustration' is the definition.
The definition suggests a past participle verb which matches the answer.
'small hard blocks carelessly handled' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'hard' becomes 'h' (abbreviation used in pencil classifications).
'blocks' indicates putting letters inside (the inside letters form a 'blockage').
'carelessly handled' becomes 'pawed' (I've seen this before. I am not sure about the 'carelessly' bit.).
's'+'h'='sh'
'sh' put into 'pawed' is 'PSHAWED'.
'as' acts as a link.
Can you help me to learn more?
(Another definition for pshawed that I've seen is " expressed disgust".)