# Accepted definitions of 'transparent' and 'translucent' (WRT Optics)

**URL:** <https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014>\
**Category:** In My Humble Opinion\
**Created:** [March 22, 2018, 8:35am UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014 "2018-03-22T08:35:08Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\
**Post date:** [March 22, 2018, 8:35am UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014/1 "2018-03-22T08:35:08Z")

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So I got into a bit of a nerd fight in the comments section of one of my YouTube videos last night. Someone was wrong on the internet, or at least I believe so - but I just want to check whether my understanding of these terms is correct, and whether they are universally accepted.

The context was: a small laser engraver - and in the the video, I mentioned ‘_ **transparent green acrylic** _ to protect your (remaining) eye from the laser’.

Someone commented that I should look up the meaning of the term ‘transparent’  
I was initially unsure whether they maybe just didn’t realise that the object was clear green acrylic, covered (at the time of handling) with opaque paper protective film, but no - they responded with an assertion to the effect “if it’s green, it’s not transparent - you mean translucent”.

I responded to say that no, translucent is a term meaning that something transmits diffused light, but you can’t see through it - like frosted glass - and that transparent objects _can_ be tinted - because the property of transparency relates to being able to see objects clearly through something.

So my notion of these terms is:  
Transparent: Objects behind it can be clearly seen; so glass, water, whisky, sunglasses and many types of good quality gemstones are transparent, regardless of their tint or colour  
Translucent: Light passes through it, but is diffused or scattered - objects behind it cannot be clearly seen. Frosted glass, tissue paper, supermarket plastic carrier bags are translucent

Am I right? Is there any part of the world that has different established definitions for these terms?

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**Author:** ![WotNot](https://avatars.discourse-cdn.com/v4/letter/w/e19b73/32.png) [@WotNot](https://boards.straightdope.com/u/WotNot)\
**Post date:** [March 22, 2018, 9:12am UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014/2 "2018-03-22T09:12:14Z")

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Your definitions are what I’be always understood the words to mean. Looks like dictionaries agree, too (but you knew that).

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**Author:** ![Enola\_Gay](https://avatars.discourse-cdn.com/v4/letter/e/3ab097/32.png) [@Enola\_Gay](https://boards.straightdope.com/u/Enola_Gay)\
**Post date:** [March 22, 2018, 9:17am UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014/3 "2018-03-22T09:17:16Z")

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Spot on.

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**Author:** ![Heckity](https://avatars.discourse-cdn.com/v4/letter/h/a5b964/32.png) [@Heckity](https://boards.straightdope.com/u/Heckity)\
**Post date:** [March 22, 2018, 9:22am UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014/4 "2018-03-22T09:22:49Z")

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I wholeheartedly agree with you. If you can see through the object in question it is transparent, regardless of features like colour. Stained glass comes in many colours and textures. Some greens are transparent and some are translucent. I would say the textures are properties and the colours are features but perhaps those terms create a whole new area of debate.

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**Author:** ![Heracles](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heracles/32/487_2.png) [@Heracles](https://boards.straightdope.com/u/Heracles)\
**Post date:** [March 22, 2018, 10:48am UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014/5 "2018-03-22T10:48:53Z")

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I agree on the green thing.

However, my definition of translucent includes transparent (like rectangle includes square). So my kitchen window is translucent because it’s transparent. I know (French) dictionaries insist that translucent means frosted. Let them!

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**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\
**Post date:** [March 22, 2018, 3:36pm UTC](https://boards.straightdope.com/t/accepted-definitions-of-transparent-and-translucent-wrt-optics/811014/6 "2018-03-22T15:36:19Z")

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> [@Heracles](#):
>
> I agree on the green thing.
> 
> However, my definition of translucent includes transparent (like rectangle includes square). So my kitchen window is translucent because it’s transparent. I know (French) dictionaries insist that translucent means frosted. Let them!

That’s interesting, because whilst I think a semantic literal understanding of the term (trans = through, lucent = to shine) would agree with your definition, it does seem that most of the (English) dictionaries and references also state diffusion or scattering as an explicit property of translucence.
