Word of mouth

[Ju]

1. Word-of-mouth

Given or done by people talking about something or telling people about something:
Eg. We get most of our work through word-of-mouth recommendations.

2. Word of mouth

in speech but not in writing:
Eg. All the orders were given by word of mouth so that no written evidence could be discovered later.

The above 2 phrases mean different, am I right?

Thanks.

 

[tedmc]

The hyphenated phrase is an adjective whereas word of mouth is a noun, an idiom.

 

[GoesStation]

Number 2 is perfectly acceptable in formal writing.