What clod named clouds?

The romantic poet, Percy Bysshe Shelley, described clouds most beautifully as the …

… daughters of Earth and Water and the nurslings of the Sky.

The word comes from Old English and from a most unpoetic and surprising source—originally it meant a lump of rock. It is closely related to other words, its brother, clod, means a lump of soil and its cousin, clot, a lump in a liquid.

So how did these light and airy things manage to get a name related to clods and clots? The probable explanation is that large, dense cumulus clouds were thought to resemble lumps of rock so took the name, cloud. Lumps of rock, then, were left being called lumps of rock.

Meteorologists have a named convention that is very ordered and logical way as you might expect. The main types have good scientific names chosen from solid Latin roots:

Alto – high cloud – from Italian for high and from Latin Altus;

Cirrus – thin, wispy cloud – from Latin for curl, fringe;

Cumulus – tall, fluffy cloud – from Latin for a heap or pile;

Nimbus – rain-bearing cloud – from Latin for raincloud; and

Stratus – broad and flat  – from Latin for spread out.

These basic type names can be combined to describe in-between types, for instance, a cumulonimbus is a cumulus bearing rain or a cirrostratus is thin and wispy and spread out.

However, there appears to be some mischievous meteorologists out there who find this all far too dull. Watch out for:

Mammatocumulus or breast clouds (from Latin mamma for breast or udder);

Tuba clouds that look like trumpets hanging from cumulus; and

Scud clouds that shoot along under storms (scud, related to scuttle, means to move quickly and perhaps comes from the Middle English scut meaning to race like a hare).

You can only think that Shelley would have been proud of the imaginative meteorologists.