valid-, val-, vale-, -vail, -valent, -valence
(Latin: valere, to be strong, to be well, to be worth; strong; power, strength; and "fare well" [go with strength])
Quot linguas calles, tot homines vales.
As many languages as you know, so many separate individuals you are worth.
You are worth as many different people as the number of languages you know. Attributed to Charles V, Holy Roman Emperor.
solar energy equivalent
A statement of the amount of energy received from the sun in terms of some conventional energy unit; such as, kilowatt-hours, barrels of oil, tons of coal, etc.; used to describe the relative ability of solar energy to fulfill contemporary energy requirements as compared to fossil fuel sources.
Sexually potent in the standing position only.
Sexually potent only when supine (lying on the back with the face upward).
Testis oculatus unus plus valet quam auriti decem.
One eye-witness is worth more than ten ear-witnesses.
Testis oculatus unus plus valet quam auriti decem
In law, One eye-witness is worth more than ten ear-witnesses.
Farewell for the last time.
Also, Supremum vale or "Farewell for the last time"; that is, just before death takes over.