Word Study
constantan
CIDE DICTIONARY
constantan, n.
a copper-nickel alloy composed of approximately 55 per cent copper and 45 per cent nickel, with high electrical resistance and a low temperature coefficient; it is used as resistance wire and in thermocouples.
"It has a resistance factor -6 ohm-cm at 0-6 ohm-cm for pure copper and 7.8 x 10-6 ohm-cm for pure nickel. It is similar to the alloy Eureka, which has a -6 ohm-cm. Handbook of Ch. 61 . " [WordNet 1.5]
OXFORD DICTIONARY
constantan, n. an alloy of copper and nickel used in electrical equipment.
Etymology
constant + -an
For further exploring for "constantan" in Webster Dictionary Online