word of mouth

"Word of mouth" is when people tell their friends, family, etc. about something and recommend it. Things that become popular this way are said to "spread through word of mouth".

"Word of mouth" is especially used to talk about things becoming popular without being advertised.

You can also talk about something having "good word of mouth":

That new Mexican restaurant on Falcon Street has good word of mouth.

This phrase appears in these lessons: