Nervous part of speech (5)
I believe the answer is:
tense
'nervous' is the definition.
(similar in meaning)
'part of speech' is the wordplay.
'part' becomes 'te' (te is a kind of part).
'of speech' becomes 'nse' (I can't explain this - if you can you should give a lot more credence to this answer).
'te'+'nse'='TENSE'
Can you help me to learn more?
(Other definitions for tense that I've seen before include "past, say" , "Taut - timely verbal indication" , "Worried" , "show strain" , "far from comfortable" .)