subtle prettiness is when someone is pretty but it isn't obvious. When u look at them, they seem pretty but if u really stare at them for a while, they are actually really beautifil.
hope this helps
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2278018Retrolisthesis (backwards slippage of one vertebral body on another) has historically been regarded as an incidental...
The term 'subtle' has a few senses: 1: difficult to detect or grasp by the mind or analyze; 2: working or spreading in a hidden and usually injurious way; 3: able to make fine distinctions