Sloths are slow.
Sloth, meaning laziness, is also one of the Seven Deadly Sins in Christianity.
Unsurprisingly enough, the sin came first, and the animal was named after it, because it seems so lazy. They’re not actually lazy of course, just slow. Though some individual sloths probably are lazy, but it’d obviously be unfair to tar them all with the same brush.
It’s a funny word, sloth, and not one we really use beyond these two contexts. Where does it come from?
The answer is actually surprisingly straightforward, and you might be able to figure it out if you look at the word. Sloth is a now-obsolete noun form of the word slow. Originally it was slowth. Adding the suffix -th was once a common way to form nouns of action, quality, or state from adjectives. We can still see a few examples in English: warmth, strength, length, width, and so on. Slowth gradually became sloth, probably because the former is a bit awkward to say. And because sloth isn’t clearly linked to slow, its meaning drifted a little to mean lazy. And because people didn’t realise that it was the noun form of slow, slowness came into being as the noun form instead (and it does sound better than slowth, doesn’t it?).
So even though sloths got their name because they seemed lazy, it’s kind of appropriate that their name is sloth, as they are just slow, harking back to that original meaning.
Also, they’re very cute.
English-Language Thoughts 
Poor sloth – it gets a bad reputation for laziness! I have one that lazes around on the side of my teacup. You fill him with tea leaves because he’s a tea infuser! So, given the origin, should sloth rhyme with moth or growth?
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That’s a good question. Rhyming with “moth” is more common because that pronunciation feels more logical because of the spelling, but both pronunciations are accepted.
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I love learning new things, especially about different religions! Sloths are definitely cute though…
FATIMAH • ROSEYGOLDBOX
http://www.roseygoldbox.blogspot.co.uk
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Very interesting
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Always learn something. Never surprised how we twist words and some become negative and other positive over time.
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This is fascinating! I had never made the connection between the adjective and simply adding the ‘th’ to make the noun.
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Neither did I, then once I learned about it it seemed so obvious!
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Yes it does! I love it when that happens 🙂
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I didn’t know the word sloth came from slowth, and it makes sense why sloths were named that!
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