Most antifreeze solutions contain high levels of ethylene glycol, an ingredient that, once metabolized, is extremely toxic to dogs and cats. Pets are often attracted to the liquid because of its sweet taste. Even small amounts can be lethal to animals.
Wiktionary(0.00 / 0 votes)Rate this definition: arduous(Adjective) Needing or using up much energy; testing powers of endurance. The movement towards a peaceful settlement has been a long and arduous political struggle.
Examples of arduous in a sentence. 1  Traveling for several days by train, stagecoach and horseback, they would reach Mariposa Grove, a stand of some 200 ancient giant sequoias, where they would rest before embarking on an arduous descent via 26 switchbacks into the valley.