reticule

[H]er hair had been used to create the reticule in the famous Norden bombsight—a top-secret WWII targeting device.

When reading the note, and arriving at an assurance of Helen's absence, Lady Anne had indignantly crushed it in her hand, and thrust it into her reticule, but, on her return home, whilst Fanchette was industriously employed upon her hair with the invaluable liquid dye, she drew out the rumpled paper, and read the concluding paragraph.