According to both Google Trends and my observations of the world, the word emoticon has been decreasing in usage of late, in favor of emoji. Both describe a small digital picture often used on the Internet, and both sound similar, but the roots are different, etymologically speaking. Additionally, a schism in definition caused "emoticon" to mainly mean characters created out of text, and "emoji" to be ready-made images. Emoticon, which was coined by 1994, is a portmanteau of the words emotion and icon, which is pretty self-explanatory. Emoji is much cleverer. Shigetaka Kurita, the man who invented the modern pictorial variation, named them that as a sort of play on words: it sounded like both emoticon and kanji, a Japanese system of writing, but actually combined the words e, meaning "picture", and moji, meaning "character". Best pun since Shakespeare, in my opinion. E is very simple and therefore has a very simple etymology. It probably comes from a Chinese word meaning "drawing" and sounding like huay, which always sounded like that and meant that. Moji, meanwhile, is thought to be from Middle Chinese midzi, meaning "writing-character", also without much change before that. So an emoji carries the hidden meaning of "drawing-writing-character"!
Adam Aleksic, a leading contender for valedictorian of his high school, is a 210-month-old boy with disturbing interests in etymology, vexillology, geography, and law. Adam would like to one day visit Tajikistan and probably isn't spying for the Kyrgyz government.
The Etymology Nerd