Delete

    Mode

    Edit Mode

    Menu

    Armature ‣ Delete ‣ Bones

    Hotkey

    This tool delete selected bones, selected joints are ignored.

    If you delete a bone in a chain, its child(ren) will be automatically re-parented to its own parent, but not connected, to avoid deforming the whole armature.

    Dissolve

    Reference

    Edit Mode

    Menu

    Armature ‣ Delete ‣ Dissolve

    Hotkey

    Ctrl-X