The adjective secret is used to describe things that are either done without the knowledge of others, such as secret negotiations, or that are working to escape notice or observation, such as secret police. It’s also used to describe things that are secluded or sheltered, such as a secret hiding place—and things that are known by only a few, such as a secret password. The synonym clandestine is used to describe operations, meetings, and programs that are done in or executed with concealment, especially for the purposes of subversion or deception. If you’re looking to describe the activities of international spies or stealth programs run by the military or a government, clandestine is the perfect choice.

The verb drop suggests an abrupt descent or downward trajectory. It can be used of items that are falling in a literal sense, such as rain from the sky or acorns from a tree, or of immaterial things—such as prices or temperatures. The synonym plummet suggests an even more rapid and steep descent, as if being pulled down by a weight. There's a reason for the extra weight: the word plummet (noun) originally referred to a piece of lead or some other weight attached to a line, used for determining the perpendicularity or depth of something. So, when prices or temperatures plummet, they decrease sharply and dramatically, as if being pulled down by something heavy.

Roses are red, violets are blue—poets they’re called, but you can call them bards, too. Bard is an old-fashioned synonym for poet. In medieval times, the noun bard referred to a person who composed and recited epic or heroic poems, often while playing the harp, lyre, or the like. Earlier still, the term was also used to refer to one of an ancient Celtic order of composers and reciters of poetry. By the time William Shakespeare was rattling off verses, bard was in circulation as a more general term for a lyric or epic poet—and eventually the term came to be associated with Shakespeare himself, who came to be known variously as the Bard of Avon, or, more definitively, the Bard.