thunderhead

/ˈθʌndɚˌhɛd/

Etymology

From thunder + head.

thunderhead means the top portion of a cumulonimbus cloud, which tends to be flattened or fibery in appearance, and may be indicative of thunderstorm activity. Lexicurio rates it Sui generis — a strength score of 88 out of 100.

Why this word is great

THUNDERHEAD — [Noun] The anvil-shaped upper portion of a cumulonimbus cloud, heralding the imminent development of thunderstorms. Its etymology is bluntly descriptive: from *thunder* (the loud rumbling sound following lightning) + *head* (the top or foremost part). Unlike “cumulonimbus,” which names the entire towering cloud system, or “thundercloud,” a general term for any ominous mass, “thunderhead” points specifically to that majestic, spreading crown. It is the great frozen forge in the sky, a colossal anvil of ice crystals catching the last slant of sun while the earth darkens; it is the storm’s silent, boiling caldera; it is the visible mind of the tempest, thinking in lightning. We name the part to isolate the moment of awful, beautiful transition before the sky breaks open.

noun

The top portion of a cumulonimbus cloud, which tends to be flattened or fibery in appearance, and may be indicative of thunderstorm activity.“Half the sky was checkered with black thunderheads, but all the west was luminous and clear:”