(kon′stənt) adjective
1. Steady in purpose; resolute; persevering; faithful.
2. Steady in movement.
3. Long–continuing, or continually recurring.
4. Invariable.
5. Obs. Firm; positive; consistent.
—noun
1. That which is permanent or invariable.
2. Math. A quantity which retains a fixed value throughout a given discussion.
3. In the sciences, any characteristic of a substance, event, or phenomenon, numerically determined, that remains always the same under specified conditions, as gravitation, the velocity of light, the melting or freezing point, etc. See synonyms under CONTINUAL, PERPETUAL. [<L constans, -antis, ppr. of constare <com- thoroughly + stare stand]
—con′stant·ly adverb

(kon′stənt, Fr. Kô·stä′)
A masculine personal name. Also Lat. Con·stans (kon′stənz), Pg., Sp. Con·stan·ci·o (Pg. kô·stä′sē·ō, Sp. kōn·stän′thē·ō). [<L, constant, firm]

(kô·stä′), Jean Joseph Benjamin,
1845–1902, French portrait painter.
—Constant de Re·becque (də rə·bek′), Benjamin,
1767–1830, French writer and statesman.