orange non-italic keywords

[Joe Austin]

I have two images with entirely different sets of keywords.    Each image has a few keywords that appear in orange when viewed in the Keywords Panel for the current image.

If I select both images then I see the gray italicized keywords for words in either image, but I also see the orange, non-italicized, words from both images. 

On the Keywords Panel help page, I see that italics represent words  not in all of the selected images , and non-italic words indicate words found in all of the selected images.

What do orange words indicate?     Why do they appear as non-italics when they are only in one of the two selected images?

[Mario]

Synonyms.
Check your thesaurus.

[Joe Austin]

Ok, thanks.   

But shouldn't the synonyms appear italicized when they don't apply to all images in a selection?

I also see that I have one keyword with four synonyms defined , but only two appear in the  orange keywords, why don't the other two appear?

[Mario]

Please file a bug report so I can look into this.
Please state which keyword you mean, and attach your thesaurus and a sample image which contains the keywords you used for your test (or send this to me by email). The Keyword Panel looks up synonyms from the keyword, and if they are found depends entirely on the input keyword and your thesaurus and how you have configured things like group levels, exclusions and the like...