Yes, narrow is a Scrabble word!

Verb

1. Make or become more narrow or restricted

2. Define clearly

3. Become more focus on an area of activity or field of study

4. Become tight or as if tight

Adjective

1. Not wide

2. Limited in size or scope

3. Lacking tolerance or flexibility or breadth of view

4. Very limited in degree

5. Characterized by painstaking care and detailed examination

Noun

1. A narrow strait connecting two bodies of water