kaŝperanto:Interesting, I was assuming that if they made such regular usage of it that it was at least a semi-official word. It took me awhile to find that ipernity thread to figure out what tabasami meant, and I believe they even use it in their older albums.

Here's a rule of thumb -- don't assume a word is common if you hear it in music, even if the same band uses it repeatedly. Poets and musicians tend to be more creative with their word usage than the general community. For what it's worth, the band Dolchamar also makes use of non-standard vocabulary (and orthography!) in their albums, so La Perdita Generacio is hardly alone in this. If you hear a word you don't know and you have a hard time finding it when you look it up online, or if you find it only in reference to the same source where you heard it from, that should raise a red flag that maybe this word is rare or non-standard. That isn't to say that you should never use it, but you should be aware that if you choose to use this word, you may not be understood, and you should have a less controversial backup word in mind (rideti, in this case) in case you need to say your sentence again in a way everyone can understand.

sudanglo:In English however we distinguish between those actions that make a sound like laugh, chuckle, guffaw and those like smile and grin that don't. So for English ears rideti for smile is wrong, an illogical calque.

Illogical because Ridegi, and Ridi are sounds and Rideti isn't.
...
Of course if ridi can be silent in Esperanto then rideti can be too, but silenta rido seems at very least poetic licence, if not actually contradictory. You certainly can't have a silenta ridego.

I may be wrong about the meaning of the English words, because I have mapped them too simplistically onto my Sweedish concepts. For me, the basic difference between ridi and rideti is not a question about sound, but about the muscular activity. If it is strong enough to cause rhythical movements, then I use ridi (or ridegi), otherwise rideti. The sound can be surpressed with ridi - and even with ridegi - simply by opening the vocal cords and letting the air come out freely, while the chest is moving paroxysmally.

A test as to whether rideto has become frozen by usage into a narrower meaning, would be to ask people to explain the difference between an eta rido and a rideto.

In my searches in the Tekstaro I did not see any specific reference to rideto having a sound. There are quite a few instances where there is explicit references to the contortion of the face or to the lips.

erinja:
Here's a rule of thumb -- don't assume a word is common if you hear it in music, even if the same band uses it repeatedly. Poets and musicians tend to be more creative with their word usage than the general community. For what it's worth, the band Dolchamar also makes use of non-standard vocabulary (and orthography!) in their albums, so La Perdita Generacio is hardly alone in this. If you hear a word you don't know and you have a hard time finding it when you look it up online, or if you find it only in reference to the same source where you heard it from, that should raise a red flag that maybe this word is rare or non-standard. That isn't to say that you should never use it, but you should be aware that if you choose to use this word, you may not be understood, and you should have a less controversial backup word in mind (rideti, in this case) in case you need to say your sentence again in a way everyone can understand.

I guess it is true that artistic folk tend to be more creative than usual (thus we have "artistic license" ). I think it's very witty how Dolchamar titled their album "Trejn Tu Noŭer".

Rugxdoma:
I may be wrong about the meaning of the English words, because I have mapped them too simplistically onto my Sweedish concepts. For me, the basic difference between ridi and rideti is not a question about sound, but about the muscular activity. If it is strong enough to cause rhythical movements, then I use ridi (or ridegi), otherwise rideti. The sound can be surpressed with ridi - and even with ridegi - simply by opening the vocal cords and letting the air come out freely, while the chest is moving paroxysmally.

That is a good distinction to make. I can smile as big as I want, but it isn't laughter until I start rhythmically contracting my diaphragm.

sudanglo:A test as to whether rideto has become frozen by usage into a narrower meaning, would be to ask people to explain the difference between an eta rido and a rideto.

In my searches in the Tekstaro I did not see any specific reference to rideto having a sound. There are quite a few instances where there is explicit references to the contortion of the face or to the lips.

That's a good idea, but isn't there already a minor distinction between "eta X-o" and "X-eto"? Doesn't the affix generate a stronger bond between the meanings?

sudanglo:
In my searches in the Tekstaro I did not see any specific reference to rideto having a sound. There are quite a few instances where there is explicit references to the contortion of the face or to the lips.

Perhaps it would then be better to modify "ridi" instead, to give the meaning of the rhythmical varieties which are not considered as full laughter. According to the Lernu-vortaro chuckle is "subridi".
To find out if Englich really is putting more emphasis on the existence of accompanying sound compared to what Swedish does, I googled "laughed silently", and found 7370 occurances, while the Swedish equivalent "skrattade tyst" gave 8920. This is not a convincing difference, not even considering that Swedish is a far smaller language in the google-space. (Of the English "trafoj" quite a number were from Genesis 18:12, which in the Swedish translation has the word which is normally translated as "smiled".) The Esperanto equivalent "Ridis silente" gave one search result. It was from "Vere aux Fantazie" in the Lernu-library.

Whatever reality silent laughter corresponds to it is derivative of the fact that laughter usually makes a noise. Just as 'he silently crept into the room' makes sense only because footsteps normally make a sound.

A silent or noisy smile makes no sense. And I would be flabbergasted to read of a silenta or brua rideto.