The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
wer-4
DEFINITION:
To cover. Derivatives include overt, cover, warranty, garage, garrison, and garnish. I. Basic form *wer-.1.weir, from Old English wer, dam, fish trap, from Germanic *wer-jn-.2. Compound form *ap-wer-yo- (*ap-, off, away; see apo-). aperient, apéritif, aperture; overt, overture, pert, from Latin aperre, to open, uncover. 3. Compound form *op-wer-yo- (*op-, over; see epi). cover, operculum; kerchief, from Latin operre, to cover. 4. Suffixed form *wer-tro-.ambarella, from Sanskrit va, enclosure, from lengthened-grade derivative *vrt(r)a-. II. O-grade form *wor-.1.warn, from Old English *war(e)nian, to take heed, warn, from Germanic *war-nn.2a. (i)guaranty, from Old French garant, warrant, authorization; (ii)warrant, warrantee, warranty, from Old North French warant, warrant, and warantir, to guarantee; b.garage, from Old French garer, to guard, protect; c.garret, garrison, from Old French g(u)arir, to defend, protect; d.warren, from Old North French warenne, enclosure, game preserve; e.garment, garnish, garniture, from Old French g(u)arnir, to equip. a–e all from Germanic *war-.3. Suffixed form *wor-o-.a. Germanic *warn-, protector, in compound *burg-warn- (see bhergh-2); b.barbican, from Old Iranian compound *pari-vraka-, protective (*pari-, around; see per1). (Pokorny 5. er- 1160.)
n-. 2. Compound form *ap-wer-yo- (*ap-, off, away; see apo-). aperient, apéritif, aperture; overt, overture, pert, from Latin aper
re, to open, uncover. 3. Compound form *op-wer-yo- (*op-, over; see epi). cover, operculum; kerchief, from Latin oper
a
, enclosure, from lengthened-grade derivative *v
er- 1160.) 
