Not really. That's like saying that all lamps over 300 watts are to be called lamps and those less than 300 watts are to be called light bulbs. A difference between control voltage and switching voltage isn't really a discriminator either.
Is the "condenser" in the ignition of your pre-1980s car not a capacitor, just because the auto mechanic calls it by that name?
There is a difference. Contactors are usually used when driving motors. They have a higher voltage rating to prevent arc-over when stopping a motor. Relays are often used in control circuits and have lower voltage ratings. N.B. There is a voltage rating for the coil that pulls-in the contacts, and a different voltage / current rating for the contacts that drive the load..
In his keynote address at the RAPID 2015 conference last week, Made In Space CTO Jason Dunn gave an update on how far his company and co-development partner NASA have come in their quest to bring 3D printing to the space station -- and beyond.
On Memorial Day, Americans remember the sacrifices the US armed forces have made, and continue to make, in service to the country. All of us should also consider the developments in technological capabilities and equipment over the years that contribute to the success of our military operations.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.