n.
(pl. phenomena)
- a fact or situation that is observed to exist or happen, especially one whose cause is in question.
- Philosophy the object of a person's perception.
- a remarkable person or thing.
Usage
The word phenomenon comes from Greek, and its plural form is phenomena. In standard English it is a mistake to treat phenomena as if it were a singular form.
Etymology
C16: via late L. from Gk phainomenon ‘thing appearing to view’, based on phainein ‘to show’.