(philosophy) An abstract archetype of a given thing, compared to which real-life examples are seen as imperfect approximations; pure essence, as opposed to actual examples.

(informal) A very creative person; someone who is always able to come up with fresh ideas.

A concept which is transmitted between people via networks (especially the Internet) generally without the knowledge or consent of the originator, and which may be modified as it is passed on.

(metaphysics) An idea separated from a complex object, or from other ideas which naturally accompany it; as the solidity of marble when contemplated apart from its color or figure.

(informal) To not know; to have no idea.

(emphatic) I don't know. / Indicates that the speaker is completely ambivalent about something.

Used to express regret for a foolish impromptu or impulsive past action.

prediction market