Meaning

• To occur or take place.

  "Let me tell you how it happened."

• To happen to; to befall.

• (with infinitive) To do or occur by chance or unexpectedly.

  "Do you happen to have an umbrella?"

• (followed by on or upon) To encounter by chance.

Meaning

• (of a place) Busy, lively; vibrant, dynamic; fashionable.

  "This is a happening place tonight!"

• (of a person or product) Trendy, up-to-the-minute.

  "He is a real happening guy."