Important to make your mark when I don't have a pen? (11)
I believe the answer is:
significant
'important' is the definition.
(I know that important can be written as significant)
'make your mark when i don't have a pen?' is the wordplay.
'make your mark' becomes 'sign' (as in providing a signature).
'when' becomes 'if'.
'i' becomes 'a'.
'don't have' suggests deleting specific letters.
'pen?' becomes 'icant' (I can't explain this - if you can you should give a lot more credence to this answer).
'sign'+'if'+'a'='signifa'
'signifa' with 'a' removed is 'signif'.
'signif'+'icant'='SIGNIFICANT'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for significant that I've seen before include "worthy of consideration" , "Meaningful" , "Sort of mathematical figure" , "Material" , "Consequential" .)