The verb daresay means (1) suppose, or (2) presume to say. For instance, if you think daresay means something else but are not sure what, you might comment, “I daresay this post is wrong,” or “I daresay you don’t know what you’re talking about!” It is one word, and has been so for centuries, and though it has an archaic ring, it remains useful and appears fairly often for an archaism.
His foray on to the Temple Mount was not his first and I daresay will not be his last. [Jewish Chronicle]
That’s a powerful thing, more powerful, I daresay, than the draw of Facebook and Twitter. [GadgetBox]
The old building sported high ceilings and wooden panelling; I daresay the ghosts of highwayman lurked in its shadows. [Independent]
I daresay, even if you do love the woman’s work, her debut book may still leave you with a bitter taste in your mouth. [The Yorker]