Sodium borohydride (NaBH4) is a basic compound. It is a reducing agent and a source of hydride ions (H-), which can react with water to form hydroxide ions (OH-) and hydrogen gas (H2). The reaction can be represented as:

NaBH4 + H2O → NaBO2 + H2 + OH-

The hydroxide ions produced make the solution basic. The basicity of sodium borohydride is also influenced by the presence of the borohydride anion (BH4-), which can act as a weak base by accepting protons (H+).

In summary, sodium borohydride is considered a basic compound due to its ability to release hydroxide ions and accept protons, resulting in an increase in the pH of the solution.