What part of speech is interchangeability?

Interchangeability can be categorized as a noun.

Parts of speech

• 1. interchangeability is a noun, singular of interchangeabilities.

Inflections

Noun

• Singular

  Plural
• interchangeability 

  interchangeabilities 

• Singular: interchangeability 
• Plural: interchangeabilities 

What does interchangeability mean?