Proto-Indo-European root meaning "knee; angle."

It forms all or part of: agonic; decagon; diagonal; geniculate; genuflect; genuflection; -gon; goniometer; heptagon; hexagon; knee; kneel; octagon; orthogonal; pentagon; polygon; trigonometry.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit janu, Avestan znum, Hittite genu "knee;" Greek gony "knee," gōnia "corner, angle;" Latin genu "knee;" Old English cneo, cneow "knee."

Proto-Indo-European root, probably originally "jaw, jawbone," but also forming words for "chin, cheek." It forms all or part of: chin; Compsognathus; gnathic; gnatho-.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit hanuh "jaw," Avestan zanu- "chin;" Armenian cnawt "jawbone, cheek;" Lithuanian žándas "jawbone;" Greek genus "chin, lower jaw," geneion "chin;" Old Irish gin "mouth," Welsh gen "jawbone, chin;" Old English cin, "chin."

"act of bending the knee," especially in worship, early 15c., genu-fleccion, from Medieval Latin genuflectionem (nominative genuflexio) "bending of the knee," noun of action from past-participle stem of Late Latin genuflectere "genuflect," properly genu flectere "to bend the knee," from Latin genu "knee" (from PIE root *genu- (1) "knee; angle") + flectere "to bend" (see flexible).

"pertaining to the jaw," 1882, with -ic + Greek gnathos "jaw, cheek," properly "the lower jaw," from PIE root *genu- (2) "jawbone, chin."

"having knots or joints; bent like a knee," 1660s, from Latin geniculatus "having knots, knotted," from geniculum "little knee, knot on the stalk of a plant," diminutive of genu "knee" (from PIE root *genu- (1) "knee; angle"). Related: Geniculation (1610s).

1560s, from French heptagon, from Greek heptagonon, from hepta "seven" (see septi-) + gōnia "angle, corner" (from PIE root *genu- (1) "knee; angle"). Related: Heptagonal.

before vowels gnath-, word-forming element meaning "jaw, mouth part, beak (of a bird)," from Greek gnathos "jaw," from PIE root *genu- (2) "jawbone, chin."

word-forming element meaning "angle, corner," from Greek gōnia "corner, angle," from PIE root *genu- (1) "knee; angle."

instrument for measuring solid angles, 1766, from Greek gōnia "corner, angle" (from PIE root *genu- (1) "knee; angle") + -meter. Related: Goniometry.

1560s, from Latin hexagonum, from Greek hexagonon, neuter of hexagonos "six-cornered, hexagonal," from hex "six" (see hexa-) + gōnia "angle, corner" (from PIE root *genu- (1) "knee; angle").