This character is a Other Symbol and is commonly used, that is, in no specific script.
The glyph is not a composition. Its East Asian Width is wide. In bidirectional text it acts as Other Neutral. When changing direction it is not mirrored. U+1F531 offers a line break opportunity at its position, except in some numeric contexts.
The CLDR project calls this character “trident emblem” for use in screen reading software. It assigns these additional labels, e.g. for search in emoji pickers: anchor, emblem, poseidon, ship, tool, trident.
This character is designated as an emoji. It will be rendered as colorful emoji on conforming platforms. To reduce it to a monochrome character, you can combine it with Variation Selector-15: 🔱︎ See the Emojipedia for more details on this character’s emoji properties.
The Wikipedia has the following information about this codepoint:
A trident () is a three-pronged spear. It is used for spear fishing and historically as a polearm. As compared to an ordinary spear, the three tines increase the chance that a fish will be struck and decrease the chance that a fish will be able to dislodge itself if struck badly. On the other hand, they are not so many as to overly reduce the spear's concentration of force for piercing.
The trident is the tool of Poseidon (Greek) or Neptune (Roman) used for the protection of the sea realms, the god of the sea in classical mythology. Other sea deities such as Amphitrite or Triton were also often depicted with a trident in classical art. Later, tridents were used in medieval heraldry, sometimes held by a merman or triton. In Hinduism, it is the weapon of Shiva and is known as a trishula (Sanskrit for "triple-spear").