determini

The most loaded false seam in this chapter. Esperanto has termino at rank 2,304 - a technical term, a word with a fenced meaning. It has de as an ordinary preposition. And there is a verb termini, to terminate, in the dictionaries. So determini reads as de- plus termini, and a learner who has spent this course being rewarded for splitting words will split this one.

Do not. -De is not a prefix in Esperanto; the preposition does not compound that way, and de-termini would have to mean something like "to terminate from", which is not what the word means at all. Determin- is one root, borrowed whole under Rule 15.

And here is the twist that makes it worth a page. In Latin the seam is completely real. Determinare is de- plus terminus, the boundary stone at the edge of a field, and to determine something was literally to draw a line round it. So the pieces you can see are genuinely there - they are simply two thousand years old and belong to a language that is not this one. The termino page tells the same story from the other end: a termino is a word somebody has fenced.

This is the inspiri class - a borrowed root whose Latin decomposition is honest history and dead grammar. The rule that keeps you safe is not "never split", it is: split only where both halves are Esperanto words that combine to the meaning you have. De plus termini does not.

Against the near neighbours, which is the practical part.

• Difini - to define. You state what a word or a concept means. It acts on meanings.
• Determini - to determine. You establish what a value, a cause or a fact actually is, by measuring, testing or ruling. It acts on facts and quantities.
• Decidi - to decide. You choose. It acts on actions, and it needs a person doing the choosing.

Determini la prezon is to fix the price; decidi pri la prezo is to make up your mind about it; difini la prezon would be to explain what the word price means. There is one more sense worth having: determini also covers the impersonal one, where a cause fixes an outcome - la vetero determinis la rezulton. Nothing chose anything; the weather simply settled it.

Derived forms. Determino is the act, determinado the process, and determinita means fixed or settled. Determinismo is the philosophical doctrine, with the -ism- doing its usual job on top of the borrowed root.