The noun καρπος (karpos) means fruit, but has a slightly broader compass than the word fruit does in English. It derives from a very old Proto-Indo-European root "(s)ker-", to harvest or pluck, that also gave rise to our English words "carpet", "excerpt" and the verbal element "carp" in words such as "carpology" (the biology of fruits and seeds) and "mericarp" (a particular portion of a fruit). Our noun also resulted in the name of the abundantly fruitful fish, the carp, and corresponds to the Latin verb carpo, from whence we have the familiar aphorism carpe diem, or pluck the day. From the same PIE root comes the verb κειρω (keiro), to shear or shave off.

The ultimate meaning of the word καρπος (karpos) does not appear to emphasize the mere production of fruits ex nihilo, but rather the return on an investment (namely seeds and labor). In Greek the word for wrist is also καρπος (karpos), and although it is probably a whole different word, it was probably derived from a root that means to turn around (Liddell and Scott, An Intermediate Greek-English Lexicon).

In the Bible our noun καρπος (karpos) describes the fruit of trees and plants (Matthew 3:10, Luke 12:17, John 12:24) but also the harvest of a field (2 Timothy 2:6). Our word may describe the whole produce of a project such as a vineyard (Matthew 21:41) and even one's children (Luke 1:42, Acts 2:30).

Dictionaries will state that the latter usage and the following are metaphors, but that's an auto-centric mistake. Our word is an economic term that denotes the return of an endeavor: anything that comes about after an initial investment and subsequent effort (Romans 1:13, 7:4), and that includes apples, corn, children and: deeds or works (Matthew 3:8, Luke 3:8), results or effects (hence the "fruit of the Spirit": Galatians 5:22, Ephesians 5:9, but also see Romans 15:28, Hebrews 12:11 and James 3:17), and verbal praise and thanks (Hebrews 13:15). As such, in many contexts a more proper translation of our word would be "yield" (hence the "yield" of the Spirit).

Our noun is used 66 times in the New Testament, see full concordance, and from it derive:

The noun καρφος (karphos) describes anything dry or withered (straw, twigs, wood chips). It comes from the unused verb καρφω (karpho), to dry, wither or shrivel (of skin). On rare occasions in the classics, our noun καρφος (karphos) refers to very ripe (and wrinkly) fruits, which is remarkable because of the similarity with καρπος (karpos), fruit (see above).

Hesiod once remarked that Zeus withers the proud of heart, which is remarkable because the verb σκελλω (skello), means to dry up or parch (hence our English noun skeleton), whereas the derived adjective σκολιος (skolios) means bent from dryness and calls to mind the noun καρπος (karpos), meaning wrist (see above). It should also be remembered that the mental equivalent of certainties is dry land, whereas learning and growing requires fluids (see our article on the cognitive equivalent of the hydrological cycle: νεφελη, nephele, cloud).

It's a mystery where our noun may come from (and thus what it essentially means), since it doesn't occur convincingly anywhere else in the Indo-European language basin. And that suggests (at least to us here at Abarim Publications) that our verb καρφω (karpho) may have derived from the Hebrew verb רפה (rapa), to sink down (in Isaiah 5:24, hay sinks down in flames), and thus relate to the Greek verb ρεπω (rhepo), to sink or lower. The leading κ (k) might hence be explained from the prefix כ (ke), as if or like, or even from our term's ultimate proximity to καρπος (karpos), fruit.

But whatever its pedigree, our noun καρφος (karphos) occurs in the New Testament solely in the context of the proverbial dry-bit in the brother's bothered eye, which obviously also refers to a remnant of some dry dogma (or proper decorum) that can only be cleared by lots of flowing water, and not by an even bigger lode of dogma and orthodoxy. Our noun is used 6 times; see full concordance.