- A chamber, such as the furnace of a steam locomotive, in which fuel is burned.
- A box containing a fire alarm.
- The <xref>chamber</xref> of a <xref>steam engine</xref>, or a steam <xref>locomotive</xref>, in which the <xref>fuel</xref> is burned.
- The part of a <xref>fireplace</xref> where the fuel is burned.
- A <xref>redheaded</xref> woman (by <xref>synecdoche</xref>, <xref>pars pro toto</xref>), or her red <xref>pubic hair</xref>, from <xref>box</xref> ("vagina").
- a furnace (as on a steam locomotive) in which fuel is burned