Dialect v/s Accent

What is the difference between dialect & accent?

I found that from google.

Dialect = a form of a language which is peculiar to a specific region or social group { from the Greek dialektos “discourse, way of speaking”}

Accent = a way of pronouncing a language, associated with a country, area, or social class, an emphasis given to a syllable, word, or note.{from the Latin accentus “tone, signal, or intensity”}.

When the people from India speak English, I noticed that they have a heavy India accent.

Some English words they used which I couldn’t understand because there were their local dialect mixed in English.