English
collateral
Collateral comes from Medieval Latin collaterālis, from Latin latus ‘side’, and perhaps ultimately from Proto-Indo-European *pleth₂- ‘flat’.
- Proto-Indo-Europeanc. 4500–2500 BCE*pleth₂-1‘flat’uncertain
- Latinc. 75 BCE–200 CElatus2‘side’
- Medieval Latinc. 600–1500collaterālis2
- Englishearliest quotation c. 1603–1606collateral2
attested reconstructed ? uncertain or disputed deepest recorded ancestor
- 1 Wiktionary, Latin latus
- 2 Wiktionary, English collateral
- Earliest quotation in Wiktionary’s entry: c. 1603–1606, William Shakespeare, The Tragedie of King Lear: “If by direct or by collateral hand They find…”.
Lineage
- Proto-Indo-Europeanc. 4500–2500 BCE*pleth₂-Wiktionary, Latin latus‘flat’uncertain
- Latinc. 75 BCE–200 CElatusWiktionary, English collateral‘side’
- Medieval Latinc. 600–1500collaterālisWiktionary, English collateral
- Englishearliest quotation c. 1603–1606collateralWiktionary, English collateral. Earliest quotation in Wiktionary’s entry: c. 1603–1606, William Shakespeare, The Tragedie of King Lear: “If by direct or by collateral hand They find…”
Equivalent to col- + lateral
The story
Recorded since c.1378, from Old French, from Medieval Latin collaterālis, from Latin col- (‘together with’) (a form of con-) + the stem of latus (‘side’).
Linked words
through Proto-Indo-European *pleth₂- ‘flat’
plane, flat, plate, plaza, platinum, piazza, plat, plantain, flan, plaice, 15 more
through Latin latus ‘side’
Today it means
adj Parallel, in the same vein, side by side.
Sources
Sources: Wiktionary, “collateral”; the older steps come from the Wiktionary entry for Latin latus. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.
Etymograph / Proto-Indo-European *pleth₂- / collateral