The adjectives equivalent and tantamount imply a correspondence between two or more things. Equivalent is the more general term, and it has a wider application. You might encounter it used in the context of quantities or measurements; in a recipe, for instance, if you substitute one ingredient for another, you might use an equivalent amount of the substitute. Tantamount is a far less common word, and it is used to talk about immaterial things that are equivalent in value, force, effect, or signification. The correspondence implied by tantamount is a little looser and open to interpretation—and this descriptor is almost always used with the preposition to, as in, His angry speech was tantamount to a declaration of war.
There are many ways to write. You can do so meticulously with elegant, precise penmanship, or you can scrawl—which is pretty much the opposite. The verb scrawl is defined as “to write awkwardly, carelessly, or illegibly.” If you hastily scrawl your name across a blackboard, you are writing it in a sprawling, awkward manner. The origin of this word is uncertain, but it may have been influenced by an earlier use of scrawl to mean “to scramble or crawl.” The hurried disorderliness inherent in scramble, which shares the first three letters with scrawl, is indeed what sets scrawl apart from other more measured synonyms for write, such as draft, compose, and pen.
A nickname is a name added to or substituted for the proper name of a person or place—it may be given out of affection, ridicule, or familiarity: She was such a fast runner, her friends on the playground gave her the nickname Flash. Nicknames can also be familiar (usually shortened) forms of a proper name, as Jim for James or Peg for Margaret. A moniker is a name, especially a nickname or alias. Unlike a nickname, a moniker is sometimes self-selected for a particular purpose: The lounge singer chose to perform under the moniker Lizard Lou; he felt his real name, Steven, didn’t fit the persona. Moniker is sometimes spelled monicker, but the former is far more prevalent and far less likely to raise the eyebrow (or ire) of a proofreader.