The verb invigorate is bursting with life! It means “to give vigor to” or “to fill with life and energy.” This animated term is similar to energize, but invigorate, drawing on vigor “vitality,” emphasizes healthy physical or mental energy or power. A brisk walk in mountain air will invigorate your senses; a fascinating conversation will invigorate your mind; and, applied a little more broadly, actions taken by a governing body, such as a city government, might invigorate a local economy.
The verb embroil is used to talk about involvements or entanglements of a particularly contentious or messy nature. If a person is embroiled in controversy, they are at the center of a bitter dispute or are deeply involved in a complex situation marked by discord and hostility. The more general verb involve is often used to talk about participation in something embarrassing or troublesome, but it does not convey the same degree of complication or strife.
Something that is harmful causes or is capable of causing harm (no surprises there!). Something that is pernicious causes insidious harm or even ruin. This sneaky adjective describes things that are both highly destructive and not easy to detect—often because they develop or spread gradually or under the radar. The influence of a person or entity might be described as pernicious if it puts people or things in peril. Similarly, a pernicious myth is one that impairs understanding to the point of causing harm.