It can easily get out of hand (3)
I believe the answer is:
eel
'it can easily' is the definition.
The definition suggests a singular noun which matches the answer.
'out of hand' is the wordplay.
'out of' becomes 'ee' (I can't explain this - if you can you should give a lot more credence to this answer).
'hand' becomes 'L' (abbreviation for left, as in the left-hand side).
'ee'+'l'='EEL'
'get' acts as a link.
Can you help me to learn more?
(Other definitions for eel that I've seen before include "A sea snake" , "Snake-like sea creature" , "Slippery creature" , "slipper" , "Unagi, in a sushi bar" .)