English Language: similes

as clean as a whistle

1. if someone is as clean as a whistle, they are not involved in anything illegal. 

He hasn't got a criminal record - he's clean as a whistle.

2. to be very clean. The café's as clean as a whistle, and the food's excellent.

The modern-day whistle is made of metal but in the past whistles were made of wood, particularly a reed, like those used in wind instruments such as the clarinet. In order to get a clear sound the whistle had to be free from dust & other impurities. Hence our modern expressions clean as a whistle, clean or empty.

It may well relate to steam engine locomotives where the brass, especially the whistle was always bright and gleaming.

Do you have lollypops with whistles tied to the end of the stick in the school canteen?

Have you seen Railway Station Master’s whistle?

What are wind instruments?

Is church organ a wind instrument?

Do we have wind instruments made of reed in Sri Lanka?

Have you seen steam engine locomotives?

Well, we still have a steam engine locomotive run by a private company carrying tourists in the Colombo Kandy railway line. Do you know the name of it? Ok,  you can see a photo of it in this post.

Similes

Similes are old as the hills & are used by most people almost instinctively. A simile is a figure of speech that compares two supposedly similar objects or describes a similar property that two different objects each possess.

as clean as a whistle, as white as a sheet, as drunk as a lord, as fit as a fiddle, as old as the hills

Keep you name as clean as a whistle. Do not get your name tarnished.

What's in a name? Everything.