2. Etymology: The term helicopter was borrowed from the French word hélicoptère, a word constructed from Greek heliko- and pteron, "wing". Heliko- is the combining form of helix, "spiral" that has given us helico-, which can be joined with other words and word forms to create new words.
The consonant cluster "pt" in pteron begins many Greek words but relatively few English words. English speakers unfamiliar with Greek are therefore not likely to recognize the word's elements as helico-pter. Many people divide the word into the elements heli-copter, as is shown by the clipped form "copter".