# Ped-

The word root ped- (usually in the combining forms peda-, pedi-, and pedo-) in English and various other Western languages has multiple Latin and Ancient Greek roots, and multiple meanings. Ped- (sometimes spelled paed-, pæd-, or rarely paid-, depending on the word and the language or dialect) is a root in English and many other Western languages, often with divergent spellings, such as pet-, pie-, pei-, etc.

## Meanings

Ped- conveys multiple meanings, from different Latin and Ancient Greek root words:
* 'Relating to feet', in words (e.g. pedestrian, pedicure) derived from Latin pes, genitive pedis, 'foot', from the Proto-Indo-European stem *ped- with the same meaning. Romance languages' words from this Latin root often take pie- spellings, as in medieval French and Italian piedmont 'foothill' (modern French piémont, Occitan piemont, Italian piemonte or pedemontano), and Spanish pie, pies 'foot, feet'. Many words in English and other Western languages relating to feet instead use the Greek-derived cognate pod- (e.g. podiatrist), and the Greek-derived -pus may also be used (as in octopus).
* 'Relating to children', from Greek pais (παῖς), meaning 'child', which derived from the Proto-Indo-European stem *peu-, meaning 'small', 'young', or 'few'. It is usually spelled ped- in North American English (as in pediatrics and pedophilia), and pronounced /pɛd/ or /piːd/ depending on the word. In Commonwealth English it is more often paed- (e.g. paediatrics, paedophilia), sometimes with a ligature as pæd-, and almost always pronounced /piːd/. Rarely in English, words from this root may take an initial paid- (e.g. paidology), or take only a ped- not paed- spelling (pedagogy).
* 'Relating to soil', from the Ancient Greek word for 'soil, the ground', pédon or pēdón (πέδον, πηδόν), and 'a plain or field' pedíon (πεδίον)
* 'Relating to flatulence', from Latin pēdō (infinitive pēdere, 'to fart'), the root for words relating to flatulation in several Indo-European languages;
In meanings 2, 3, and 4, the spelling remains ped- in Commonwealth English words that begin with these letters. Not all derived words do; e.g., petard (a small bomb) is from meaning 4, and entered English from Middle French pétard for the same thing (originally literally meaning 'fart', it remains an uncommon Modern French word for 'firecracker').

## Relating to children

Commonly in English, it is from the Greek pais (παῖς), originally meaning 'boy'. as well as 'child'. Contemporarily, it is more associated with the word 'child'. Words derived from this particular root are spelled paed- most cases in Commonwealth English varieties (formerly with a ligature, pæd-).
* Pederasty (paederasty), a relationship between an older man and an adolescent boy
* Pediatrics (paediatrics), the branch of medicine devoted to the medical care of infants, children, and adolescents
* Pedology (paedology, also rarely paidology), scientific study of children's behavior and development
* Pedophilia (paedophilia), a paraphilia involving sexual attraction to pre-pubescent children
** "Pedo" or "paedo", slang for "p[a]edophile"
** Pedophile Group, a Danish organization active from 1985 to 2004
** Pedobear, an Internet meme

## Relating to feet

Meanings related to feet are from Latin pes (pedis, 'foot'):
* Pedestal
* Pedestrian
* Pedicab
* Pedicure
* Pedometer
* Pedal
* Podiatrist
A Greek-derived equivalent, pod-, is often employed instead, as in "podiatry". The Greek-based -pus conveys the same meaning, as in "octopus".

## Relating to soil or plains

Ped- can also refer to soil. This root is from Greek pédon (πέδον, 'soil', 'the ground')
* Ped, a unit of soil
** Pedon, the smallest unit of soil that exemplifies its character
* Pedalfer, a type of soil containing aluminum and iron oxides
* Pedion, a single-faced crystal; also (capitalized) a brand name of tablet computer; both via analogy with a flat plain or field
* Pedocal, a subdivision of the zonal soil order
* Pedodiversity, variation in soil properties
* Pedogenesis, the process by which soil is formed
* Pedology, scientific study of soils
* Pedometrics, the study of soil formation
** Pedometric mapping, creation of maps based on soil properties
* Pedosphere, the outermost layer of the Earth, composed of soil
* Pedotope, total soil component of the abiotic matrix present in an ecotope
* Pedotransfer function, predictive functions of certain soil properties from more easily measured properties
The derived Greek word and pedíon (πεδίον, 'field or plain')

## Relating to flatulence

Another meaning, relating to flatulence, is from Latin pēdō (infinitive pēdere, 'to fart'). It does not appear in English except in loan words but is the root for words referring to flatulation in several Western languages, often in modified form such as pet-
* Petard, an obsolete type of bomb used for breaching walls and gates
* Spanish pedo and many other words in Romance languages that more literally pertain to passing gas

## Other uses

It may also be used at the end of a word, as with encyclopedia (encyclopaedia), and orthopedics (orthopaedics).
Some common English words with this derivation include:
* Pedagogy, the study of teaching and approaches to it; the theory and practice of education.