phenomenon

noun

• A thing or being, event or process, perceptible through senses; or a fact or occurrence thereof.
• (by extension) A knowable thing or event (eg by inference, especially in science)

  "An electromagnetic phenomenon."

• A kind or type of phenomenon (sense 1 or 2)

  "A volcanic eruption is an impressive phenomenon."

• Appearance; a perceptible aspect of something that is mutable.
• A fact or event considered very unusual, curious, or astonishing by those who witness it.
• A wonderful or very remarkable person or thing.
• (chiefly Kantian idealism) An experienced object whose constitution reflects the order and conceptual structure imposed upon it by the human mind (especially by the powers of perception and understanding).