What does it mean?

col*lo*quialcolloquial

Colloquial words and phrases are informal

and are used mainly in conversation.

...a colloquial expression...

ADJ

* col*lo*qui*al*ly

The people who write parking tickets in New York

are known colloquially as `brownies'.

ADV: ADV with v

(c) HarperCollins Publishers.

TRY this SITE

http://www.lingua.co.uk/English_idioms/

OXFORD UNIVERSITY PRESShttp://elt.oup.com/student/englishfile/upperint/?cc=pt&selLanguage=en

And there are many other sites which you can use for practice.Search, find and share them with your colleagues.