dwo- / Indo-European roots

1. a. two from Old English twā̆, two (nominative feminine and neuter); b. twain; twayblade from Old English twēgen, two (nominative and accusative masculine). Both a and b from Germanic *twa, two.

2. twelfth, twelve from Old English twelf, twelve, and twelfta, twelfth, from Germanic compound *twa-lif-, "two left (over from ten)" twelve (*-lif-, left; see leik^w-)

1. a. twilight from Old English twi-, two; b. zwieback, zwitterion from Old High German zwi-, twice. Both a and b from Germanic *twi-.

2. bi-¹, bis, bis-; balance, barouche, bezel, biscuit, bistort from Latin bis (combining form bi-), twice.

3. di-¹ from Greek dis (combining form di-), twice.

4. twist from Old English -twist, divided object, fork, rope, from Germanic *twis.

5. twice from Old English twige, twiga, twice, from Germanic *twiyes.

6. twenty from Old English twēntig, twenty, from Germanic compound *twēgentig, "twice ten" (*-tig, ten; see dekm̥)

7. twine from Old English twīn, double thread, from Germanic *twīhna, double thread, twisted thread.

8. between, betwixt, twixt from Old English betwēonum and betweox, betwix, between, from Germanic compounds *bi-twīhna and *bi-twisk, "at the middle point of two" (bi, at, by; see ambhi)

9. twill from Old English twilic, woven of double thread, from Germanic compound *twilic-, "two-threaded fabric"

10. Suffixed form *dwis-no-. a. twin from Old English twinn, getwinn, two by two, twin, from Germanic *twisnaz, double; b. bi-¹, binal, binary; combine, pinochle from Latin bīnī, two by two, two each.

11. Suffixed form *dwi-ko-. twig¹ from Old English twigge, a branch, from Germanic *twig(g)a, a fork.

12. Compound *dwi-plo-, twofold (*-plo-,-fold; see pel-²) diplo-, diploe, diploid, diploma; anadiplosis, diplodocus from Greek diploos, diplous, twofold.

13. Suffixed reduplicated form *dwi-du-mo-. didymium, didymous; epididymis from Greek didumos, double, the testicles.

14. Suffixed form *dwi-gha. dichasium, dicho- from Greek dikha, in two.

15. Dhivehi from Sanskrit dvīpaḥ, island, from earlier *dvi-əp-o- "having water on two sides" (*ap-, əp-, water).

1. deuce¹, dozen, dual, duet, duo, duo-; duodecimal, duumvir from Latin duo, two.

2. duad, dyad; dodecagon, hendiadys from Greek duo, duō, two.

1. Compound *du-plo-, twofold (*-plo-,-fold; see pel-²) double, doublet, doubloon, duple from Latin duplus, double.

2. Compound *du-plek-, twofold (*-plek-,-fold; see plek-) duplex, duplicate, duplicity; conduplicate from Latin duplex, double.

3. Suffixed form *du-bhw-io-. doubt, dubious; redoubtable from Latin dubius, doubtful (< "hesitating between two alternatives"), and dubitāre, to be in doubt.