planearían
Planearían is a Spanish verb form. It is the conditional tense, third-person plural form of the verb planear. Planear itself means to plan, to scheme, to devise, or to fly/glide. Therefore, "planearían" translates to "they would plan," "they would scheme," "they would devise," or "they would fly/glide." The specific meaning depends heavily on the context in which the word is used.
As an example, in the context of making arrangements, "Ellos planearían el viaje si tuvieran más tiempo"