The term alas may refer to—

• an interjection used to express regret, sorrow, grief, sympathy, or apprehension of danger or evil.
• in geomorphology, a steep-sided depression formed by the melting of permafrost; it may contain a lake.
• in zoology, a wing or winglike body part.

Also Alas! is a work of literature by Rhoda Broughton.