Second lecture on my seabird (9)
I believe the answer is:
cormorant
'seabird' is the definition.
(cormorant is a kind of seabird)
'second lecture on my' is the wordplay.
'second' becomes 'mo' (both are short periods of time).
'lecture' becomes 'rant' (I can't justify this - if you can you should believe this answer much more).
'on' means one lot of letters go next to another.
'my' becomes 'cor' (both are expressions of surprise).
'mo'+'rant'='morant'
'morant' after 'cor' is 'CORMORANT'.
Can you help me to learn more?
(Other definitions for cormorant that I've seen before include "Diving coastal bird" , "Glutton" , "Large diving bird" , "Black/white fish eater" , "Large, voracious seabird" .)