This document outlines 13 etymological theories of how words are created: 1) imitation of sounds, 2) through extended meanings, 3) as derivations from other words, 4) through compound words, 5) from root words with affixes added, 6) through changing pronunciation, 7) through changing spelling, 8) from people's or place names, 9) from shortening words, 10) from acronyms, 11) portmanteau words, 12) from borrowing foreign words, and 13) invented words.

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ETYMOLOGICAL THEORY
HOW WORDS ARE CREATED
I. By imitation of sounds (onomatopoeia)
Meow, bang, crackle, zip, ring
II. Through extended meanings
The verb fly becomes: the name of an insect, a baseball that is hit high, the
space over a theater stage
III. As derivations
From study comes student, from moon comes month
IV. Through compound words
Notebook, bedroom and mailbox are some obvious examples but also note
elbow (ell + bow) and lackadaisical (from the expression 'lackaday' which itself
derives from 'alack the day').
V. From root + affix
Prefix + root
Pro- (forward or forth) + duce (lead) = produce ("bring forth")
Root + suffix
Wonder + -full = wonderful
VI. Through changing pronunciation
Breakfast, cupboard, extraordinary
VII. Through changing spelling
Alone is from 'all one'. Felt was once used to strain liquid, so the piece of felt
used as the strainer became known as a felter, which later changed to filter.
"God be with you" was once a valediction which, over the centuries, came to
be pronounced and spelled as good-bye.

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VIII. From names (eponyms)
People's names:
The Teddy Bear is named after Teddy Roosevelt and the electrical volt after
Alessandro Volta.
Place names:
Frankfurters after named after Frankfurt, Germany, and jeans after Genoa,
Italy.
Trade names:
Kleenex, Band-aid, Jello, Xerox, Hoover
IX. From the shortening or truncating of words
Telephone becomes phone, photograph becomes photo, megabyte becomes
meg
X. From acronyms
Sonar = SOund NAvigation Ranging, laser = Light Amplification by
Stimulated Emission of Radiation
XI. Portmanteau words
Motor + hotel = motel
XII. From foreign words
Influenza (Italian), rendezvous (French), chow (Chinese), opal (Sanskrit)
XIII. Invented words
Quiz, quark