Term: letter bomb: a thin explosive device inside an envelope or package and detonated when opened
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: macrame: a relatively coarse lace; made by weaving and knotting cords
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: lithospermum: annual or perennial herbaceous or shrubby plants; cosmopolitan except Australia
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: lampyridae: fireflies
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: foray: an initial attempt (especially outside your usual areas of competence)
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: vaisya: the third of the four varnas: the commoners or yeoman farmers or mercantile and professional category
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: antique: any piece of furniture or decorative object or the like produced in a former period and valuable because of its beauty or rarity
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: staddle: a base or platform on which hay or corn is stacked
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: naval academy: an academy for training naval officers
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: encomium: a formal expression of praise
Broader: bomb: an explosive device fused to explode under specific conditions | Unrelated: bee balm: perennial aromatic herb of eastern North America having variously colored tubular flowers in dense showy heads