Thing To Be Today: colloquial.

 JRR Tolkein said that cellar-door was the loveliest word in the English language, but I think there's an argument to be made for colloquial.

Colloquial...a lovely ripple of a word.

Colloquial means to do with conversation, but there's usually an implication of informal speech - a colloquial expression is the kind of thing you might say, but that you'd not write down in an official document. 

In other words, it's the kind of language more or less everyone uses more or less all the time.

There are thousands of examples - not on your nelly is one that The Word Den investigated recently. 

Colloquial language is different from slang or non-standard language, though very nearly everyone's speech includes expressions that are all of these. 

To be colloquial is to speak without necessarily having worked out very much about the end of your sentence. At times it will involve being perhaps not strictly logical - and perhaps not strictly grammatical, too.

Importantly, it involves not caring in the slightest.

To be colloquial is to be relaxed about the language you use. To feel that the form of it isn't the most important part of the message.

And usually, of course, that's quite right.

Thing To Be Today: colloquial. This word comes from the Latin word colloqium, conversation, from com- together plus loquī to speak.