Definitions

1. noun

a masculine given name

“His name is Allen and he’s a great friend.”

2. verb

to make (something) smaller or more compact

“She had to allen down her luggage to fit it in the suitcase.”

3. proper noun

Allen, a surname and place name

“Allen, Texas is a city in the United States.”

4. noun

Allen wrench, a tool

“You’ll need an Allen wrench to fix this bike.”