Today's word is IUBEO, which is a second-conjugation verb: iubere, iussi, iussum.
Latin meaning and usage: The basic Latin meaning is to command. It can take an infinitive complement, with the person(s) commanded in the accusative. It can also take an ut (ne) clause, or a subjunctive clause without a conjunction. You can also see the person commanded in the dative as well as in the accusative.
Latin word formation: The etymology of this word might be a contraction of ius and habere. There are various compounds of the verb in Latin: adiubeo, coniubeo, etc. There are also derivatives such as iussor and its compounds: fideiussor and confideiussor.
English cognates and derivatives: The only English derivative I know of is the word "jussive" which is used to describe the use of the subjunctive in Latin - a so-called "jussive subjunctive" - which expresses a command.
Here are some examples of today's word in Latin sayings and proverbs; for more examples, see the page at the Scala Sapientiae, which also contains notes on some of the proverbs cited below:
Nos iubere volumus, non iuberi.
Si regnas, iube.
Lex universa est, quae iubet nasci et mori.
Lex iubet, aut permittit, aut vetat.
Hominem experiri multa paupertas iubet.
Lex iubet, non suadet.
Iubeat lex, non suadeat.
Deus impossibilia non iubet.
Deus nos scire pauca, multa mirari iubet.
Qui recte vivit, contemnit iussa superbi.
Non qui iussus aliquod, sed qui invitus facit, miser est.
Taurum ferre iubes, nequeam cum ferre capellam.
Dicere quae puduit, scribere iussit amor.
Fari iubes tacere quae suadet metus.
Iubet igitur nos Pythius Apollo noscere nosmet ipsos.
Nudo detrahere vestimenta me iubes.
Qui non prohibet cum potest, iubet.
Renuis quod tu, iubet alter.
Si inimicos iubemur diligere, quem habemus odisse?
Silentium non est consensus, nisi lex loqui iubeat.