Ablaut. A peculiarity of Proto-Indo-European (see below) whereby all Words containing an O in their root, have a correlate with an E, as in Greek pous, pod- "foot" and Latin pes, ped- "foot." No one knows what purpose ablaut served in Proto-Indo-European.
Alliteration. Consonant rhyme, the repetition of the same consonant, as in "Peter Piper picked a peck of pickled peppers."
Antonym. A word with the opposite meaning, as black is the antonym of white.
Aphaeresis. The loss of an initial vowel or syllable, as in the pronunciation of opossum as 'possum.
Assimilation. A consonant becoming the same as or similar to the consonant next to it, as does the N in the Latin negative prefix in- in Words like irrelevant, immature, and illegal.
Blend. The intentional creation of a word by smushing two Words together, e.g. smoke + fog > smog, motor + hotel > motel.
Case. Noun and adjective case is a feature of the grammars of some languages whereby the function of a noun is indicated by a distinct ending on the noun. For example, while tabula means "board" in Latin, "of the board" is tabulae.
Clipping. The shortening of a word by removing a syllable or two from the end (doc for doctor), the beginning (van for caravan) or both (flu for influenza).
Commonization. The conversion of a proper noun into a common noun, as the name Boycott became the English verb to boycott.
Count noun. A noun referring to a countable object, e.g. egg(s), basket(s), bike(s). Count nouns, unsurprisingly, may be counted.
Diminutive. A form of a noun that refers to a small or beloved version of the noun's meaning, as kitty is a diminutive of cat, and duckling is a diminutive of duck. English no longer produces them but they are common in languages like German, Hebrew, and Russian.
Eponym. A proper noun that becomes commonized, as Charles C. Boycott (1832-1897) is the eponym of the verb boycott.
Etymology. The study of the history of Words undertaken by etymologists.
Euphemism. An acceptable expression used in place of an unacceptable or taboo on, such as pee for the four-letter word, Gee-whiz for "Jesus," or golly for "God."
Fickle N. An N ([n] sound) that comes and goes in some Proto-Indo-European Words for reasons we don't understand. We find it in the Latin infinitive frangere "to break" but not in the past participle fractus "broken."
Fickle S. An S ([s] sound) found at the beginning of some Proto-Indo-European Words in some languages but not others, e.g. English slack comes from the same root as Latin laxus "lax."
Folk etymology. Reanalyzing a foreign Wordso that it is compatible with native Words, as the foreign-sounding Spanish cucaracha was converted into cockroach, made up of two English Words.
Frequentative. A special form of a verb which indicates that an action is repeated more than once.
Indo-European. Related to those languages of India except for the southern tip, Iran (Persian), Pakistan, Sri Lanka, the non-native languages of the Americas, the European nations except for the Basque regions of Spain, Hungary, Turkey, Estonia, and Finland. The languages that developed from Proto-Indo-European (for which see below).
Intransitive verb. A verb that does not accept a direct object, a noun or noun phrase that refers to the object on which the action of the verb is carried out: Mildred sleeps; Mildred cannot sleep anything.
Lexical. Referring to words, vocabularies, and dictionaries.
Linguistics. The scientific study of language. A linguist is not necessarily a polyglot, someone who speaks more than one language, nor a translator. He is a psychologist who studies the structure of language using scientific methods.
Mass noun. A noun referring to a substance or abstraction that cannot be counted, e.g. contemplation, leisure, languor. Mass nouns cannot be plural.
Metathesis. Two sounds switching places as in pronouncing ask, aks or the pronunciation of prescription as perscription.
Middle English. English spoken from the middle of the 12th century to about 1470.
Modern English. English as it is spoken today, since 1470.
Old English. The earliest form of English, spoken from the mid 5th century to the mid 12th century in what is today England and Southern Scotland.
Onomatopoeia. The creation of a word that sounds like the sound it represents, e.g. quack, meow, crack, slosh.
Participle. A verb form that functions as an adjective. English has a present participle, e.g. annoying in "the annoying boy," and a past participle, e.g. annoyed, in "the man annoyed by the boy."
Pejorative. Having negative connotations.
Proto-Indo-European (PIE). An ancient language that probably existed about 5000-6000 years ago in what today is eastern Poland and western Ukraine. There are no written records of the language. It has been reconstructed from the contemporary languages of India and Europe by linguists.
Rhotacism. The conversion of an S to an R, as in Latin flos, florem "flower" and genus, generis "kind, type."
Rhyming compound. A compound made up of a word followed by a word that rhymes with it, such as willy-nilly, namby-pamby, fuddy-duddy.
Synonym. A word with the same meaning as another, as couch is a synonym of sofa.
Transitive verb. A verb that accepts a direct object, a noun or noun phrase that refers to the object on which the action of the verb is carried out: The man bit the dog. Bite is a transitive verb.