Tetra
/ˈtɛtrə/noun
A combining form meaning four, used in words derived from Greek.
Did you know?The root behind tetra- comes from Proto-Indo-European *kʷetwor- “four,” the same ancient number-source that ultimately echoes through words like quarter and four in other branches.
Etymological Timeline
Proto-Indo-European
PIE
*kʷetwor-
“four”
Ancient Greek
GRK
τέτρα (tetra-)
“combining form meaning four”
Classical Greek
GRK
τετρα- (tetra-)
“used in compounds to indicate four or fourfold”
Modern English
EN
tetra-
“a prefix meaning four, used in learned compounds”