Definitions by Dr.Bsc

Titin 

Titin is a protein that in humans is encoded by the TTN gene. Titin is a giant protein that functions as a molecular spring which is responsible for the passive elasticity of muscle.
Titin is also the longest word in English language, it has 189,819 letters in total.

Teacher: Class, spell Titin.
Student: You mean that 5 letter word?
Teacher: No the full name!
Student: But that's 189,819 letters long!
Teacher: STFU and do it, get it wrong and get an hour detention for the rest of your school days here!

Titin by Dr.Bsc March 24, 2013