ko- / Indo-European roots
Examples of words with the root ko-: behind, cis-, et cetera, harass, he, hence, her, here, him, hind, hinder, hinterland, his, hither, it.
Stem of demonstrative pronoun meaning "this." Oldest form *k̑o-, becoming *ko- in centum languages.
▲ Derivatives include he1, et cetera, behind.
I. Variant form *ki-.
1. a. he1 from Old English hē, he; b. him from Old English him, him (dative of hē); c. his from Old English his, his (genitive of hē); d. her from Old English hire, her (dative and genitive of heo, she); e. it from Old English hit, it (neuter of hē); f. here from Old English hēr, here; g. hence from Old English heonane, heonon, from here; h. harass from Old French hare, call used to set dogs on, from Frankish *hara, over here, hither, alteration (perhaps influenced by *dara, thither) of earlier *hera (compare Old High German *hera, hither). a-h all from Germanic *hi-.
2. Suffixed form *ki-tro-. hither from Old English hider, hither, from Germanic *hi-thra-.
3. Suffixed form *ki-s. cis- from Latin cis, on this side of.
II. Variant form *ke-.
1. Preposed in *ke-etero- (*e-tero-, a second time, again; see i-) et cetera from Latin cēterus (neuter plural cētera), the other part, that which remains.
2. Postposed in Latin -ce (see nu-)
1. behind, hind1 from Old English behindan, in the rear, behind (bi, at; see ambhi)
2. hinterland from Old High German hintar, behind.
3. hinder1, hindrance from Old English hindrian, to check, hinder, from Germanic derivative verb *hindrōn, to keep back. 1-3 all from Germanic root *hind-, behind, attributed by some to this root (but more likely of obscure origin).
[Pokorny 1. ko- 609.]