atribui

Two senses, one shape. You atribui a work to its author - crediting, ascribing, saying where something came from - and you atribui a task or a share to somebody, which is allotting. Both take the thing as the direct object and the recipient with al: atribui la kulpon al la vetero, atribui rolon al ĉiu aktoro. The noun is atribuo, and atributo is the borrowed noun for an attribute in the grammatical and logical senses.

The false seam: it is not al plus tribui. Esperanto has the preposition al, and a learner who has met alveni and alporti will reasonably look for the same prefix here. There is no verb tribui in Esperanto for it to attach to. Atribu- came in as one root, and the doubled-up al-then-al of atribui ion al iu is your clue that no al is hiding in the verb - if one were, the sentence would not need another.

And yet the Latin really is ad plus tribuere. This is the same class of word as inspiri, where Latin in plus spirare, to breathe in, is perfectly visible and equally useless as Esperanto grammar. The history is worth having because it is a good hook: tribuere meant to divide something among the tribus, the tribes, so allotting and tributes and tribo itself all come out of one Roman piece of administration. Real etymology, no Esperanto seam.