adjective of, in, or taking place on the water.These birds live in aquatic areas.I’ve always enjoyed aquatic sports such as scuba diving.There are various aquatic events at the Summer Olympics. See the…

noun danger or risk.Ice poses the greatest hazard for winter driving. See the full entry

noun the highest point or part of anything; apex; summit.The pinnacle of the mountain is a thousand feet above the valley.The hula hoop was then at its pinnacle of popularity. See the…

adjective intended to cause or capable of causing death or extreme harm; deadly.Taken in large doses, this drug could be lethal.The huge man dealt him a lethal blow. See the full entry

noun the state or feeling of being thankful or appreciative.I don’t know how to express my gratitude for what you’ve done for me.She felt tremendous gratitude to her parents for helping her…