To lack, be wanting.
Possibly suffixed form *deu-s-
a. tire1 from Old English tēorian, tyrian, to fail, tire (< "to fall behind"), from Germanic *teuzōn;
b. deontology from Greek dein, to lack, want.
2. Suffixed form *deu-tero-. deutero-; deuteragonist, deuterium, Deuteronomy from Greek deuteros, "missing" next, second.
[Pokorny 3. deu- 219.] (For suffixed zero-grade form *du-s-, combining form of *dew-es-, a lack, see dus-.) [In Pokorny 3. deu- 219.]
To do, perform, show favor, revere.
▲ Derivatives include embellish, dynamite.
1. Suffixed form *dw-eno-. bonbon, bonito, bonny, bonus, boon2, bounty; bonanza, bonhomie, debonair from Latin bonus, good (< "useful, efficient, working").
2. Adverbial form *dw-enē. benediction, benefaction, benefactor, benefic, beneficence, benefit, benevolent, benign, ben trovato, herb bennet from Latin bene, well.
3. Diminutive *dw-en-elo-. beau, beauty, belle; beldam, belladonna, belvedere, embellish from Latin bellus, handsome, pretty, fine.
4. Possibly suffixed zero-grade form *dw-eye-. beatitude; beatific, beatify from Latin beāre, to make blessed.
5. Possible (but unlikely for formal and semantic reasons) suffixed zero-grade form *du-nə-. dynamic, dynamite, dynast, dynasty; aerodyne from Greek dunasthai, to be able.
[Pokorny 2. (deu-) 218.]