Back-formation, the development of a new form of a word by subtracting an element from an existing word, often results in additions to our word-hoard that people deem grotesque, but many words we consider members in good standing of the English language—usually verbs—have been created this way.
Derided terms of recent vintage frequently originate in business-speak: Conversate is inexplicably more complicated than the verb it supplants (converse); incentivize takes too long to speak or write, perhaps, so now we have incent; liaise awkwardly abridges the phrase “form a liaison”; protégé has inexplicably surrendered to mentee as the logical counterpart of mentor; and notate is derived from notation, because note somehow does not suffice.
However, common—and quite acceptable—noun-to-verb back-formations starting with nearly every letter of the alphabet abound, including automate (automation), babysit (babysitter), curate (curator), diagnose (diagnosis), evaluate (evaluation), flouresce (fluorescence), gamble (gambler), hustle (hustler), injure (injury), jell (jelly), kidnap (kidnapper), legislate (legislator), manipulate (manipulation), nitpick (nit-picking), orientate (orientation), peddle (peddler), reminisce (reminiscence), swindle (swindler), televise (television), upholster (upholstery), and vaccinate (vaccination).
Some less obviously produced yet patently useful back-formations include the verbs derived from nouns beg (beggar) and moonlight (from moonlighter, the slang term for one who works a second job). Back-formation of nouns from adjectives has produced diplomat (diplomatic), greed (greedy), haze (hazy), peeve (peevish), and suburb (suburban), while adjectival back-formations from nouns include complicit (complicity), decadent (decadence), and surreal (surrealism).
Two noun-to-noun developments denoting individual specimens based on words for collective concepts are ideologue (ideology) and statistic (statistics); yet another, stave, is a redundant back-formation of staves, the plural of staff in the sense of “a long stick or strip of wood.” Unit, meanwhile, derives from unity.
Cherry, pea, and tamale are back-formations based on linguistic ignorance of terms borrowed from another language or descended from a previous version of one (from, respectively, the French word cherise, the Middle English term pease, and tamales, the Spanish plural of tamal). Similar back-formations considered nonstandard (now and, one can hope, forever) include bicep (and tricep) and kudo, based on the erroneous assumption that the words biceps (and triceps) and kudos (the former from Latin and the latter from Greek) are plural.
Back-formations fill a need—whether valid or merely perceived as valid—and though some of them may, thankfully, wither from neglect, others will acquire legitimacy over time, while still others will proliferate (that word is itself a back-formation) anew.