Words can express their meaning not only by an arbitrary process of defining them, but also in the sounds and facial expressions they produce. The first is known as onomatopoeia while the second has no name of which I am aware.
Some classic examples in English for the former are to meow and squeak, the sounds that cats and rusty wheels make, respectively. If you wish to see a full chart of animal sounds, I recommend the following site: http://www.eleceng.adelaide.edu.au/personal/dabbott/animal.html. I have to note that Hungarian cats make strange noises!
Smiling requires many facial muscles as anybody who has waited for a baby to make his/her first smile would know. In English, the mi in “smile” widens the mouth perfectly while the rire in the French “sourire” does the same. The Hebrew חיוך [hi’ukh] and Russian улыбка [ulibka] create their smile from the last syllable also. Similarly, laughing is a generally a happy matter. Ignoring the difficulty of spelling it, the final f sound in “laugh” forces the lips to open as does the long e sound in the French “rire”. The Hebrew צחוק [tzhok] ends a mouth-opening long o and k sound. Of course, nothing beats the Russian words for laugh and laughter хахатать (hahatatz] and смех [smyeoch], which provides examples of both onomatopoeia and face forming words.
So, next time you learn now to say something as important as laughing or smiling, remember that the choice of words is a serious affair.