An Etymological Dictionary of Astronomy and Astrophysics

Chemistry: The number of covalent bonds which an atom can from. The sharing of electrons to form chemical bonds. → equivalence.

Etymology (EN): From → co- + valence, from L. valentia “strength, worth,” valere “to be worth; be strong.”

Etymology (PE): Ham-arzâyi, from ham-→ co- + arzâyi, from arzidan “to be worth,” arzân “worthy; of small value, cheap,” arj “esteem, honour, price, worth,” Mid.Pers. arz “value, worth,” arzidan “be worth,”
arzân “valuable;” Av. arəjaiti “is worth,” arəja- “valuable,” arəg- “to be worth;” cf. Skt. arh- “to be worth, to earn,” árhant- “worthy person;” Gk. alphanein “to bring in as profit,” alphein “to ear, obtain;” Lith. algà “salary, pay;” PIE base *alg^wh- “to earn; price, value.”