Adverb
not half (not comparable)
(Britain, slang) Greatly; to a considerable extent.
"So you fancy that girl then?" "Not half!"
The man who can keep a secret may be wise, but he is not half as wise as the man with no secrets to keep. E. W. Howe
A bird in a cage is not half a bird. Henry Ward Beecher
Plot, rules, nor even poetry, are not half so great beauties in tragedy or comedy as a just imitation of nature, of character, of the passions and their operations in diversified situations. Horace Walpole
I've actually become much, much dumber through being married and having these children. I find that I'm not half as sharp that I once was. I can't even help them with their 4th and 5th grade vocabulary and math work at this point. Patrick Warburton
One's not half of two; two are halves of one. E. E. Cummings
The best imitation in the world is not half as good as a poor original. Luise Rainer