IPA: /prɪˈzuməbli/
KK: /prɪˈzuməbli/
Used to indicate that something is assumed to be true based on available information or reasoning.
Presumably, the meeting will start at 10 AM as scheduled.
Presumably is formed from "pre-" (meaning before) and "sumere" (meaning to take). The word suggests taking something as true or likely before having full evidence or confirmation.
Think of 'taking' something ('sumere') as true 'before' ('pre-') you have all the facts — that's what presumably means.