Prefixes and the Prefix "In"


Quick Summary

Prefixes are key morphemes in English vocabulary. The prefix in, which means “in, on, or not,” appears in numerous English vocabulary words, for example: inject, influx, and insane. Prefixes do tend to have different meanings, which can be divined by context, common sense, and the process of elimination.

The Prefix 'in'

Prefixes are key parts of English words. For instance, take the word prefix itself. Pre, which means “before,” is the prefix in the word prefix. Fix, which means “fastened,” is the “stem,” or primary part of the word. Thus, a prefix etymologically is that group of letters which is “fastened before” the stem of a word; that is, prefixes begin a word.

Today we will focus on the prefix in, which can mean “in, on, or not.”

Two highly used meanings of in are “in” or “on.” Let’s look at a few examples. In, for instance, can mean “in,” such as in the words inject, to throw “in,” and influx, to flow “in.” In can also mean “on,” used in such words as inscribe, to write “on,” and invoke, to call “on.” Hence, the first primary meanings of in are “in” or “on.”

The English prefix in can also, however, mean “not.” This is a trickier part of this prefix, but once you get the hang of it, it’s highly valuable in decoding English vocabulary. Some examples of in meaning “not” include insane, or “not” sane, independent, or “not” dependent, and invalid, or “not” valid.

By using common sense, context, or the process of elimination, you will find it easier to determine whether in means “in, on” or “not.” For example, inject, throw “in,” would make no sense as “not throw.” Conversely, the word insane makes little sense as “on” sane or sane “in;” rather “not” sane is the most obvious contextual choice.

In our next rootcast we’ll discuss the prefix in again, paying attention to its spelling changes as it attaches to various different stems. Just remember for now that in can mean “in, on, into or not,” and you’ll have this prefix mastered “in” no time at all!

  1. inject: throw ‘in’
  2. influx: flow ‘in’
  3. inscribe: write ‘on’
  4. invoke: call ‘on’
  5. insane: ‘not’ sane
  6. independent: ‘not’ hanging from something
  7. invalid: ‘not’ valid

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