romantika

Two senses, and they are further apart than English lets on.

The everyday one. A romantic dinner, a romantic gesture, a romantic film: romantika vespermanĝo, romantika filmo. This is the sense the first example carries, and it is the one that pairs with amindumi, to court or to woo, at rank 2046. Note that Esperanto does not use romantika for the relationship itself; a couple are geamantoj or simply paro, and what is romantika is the evening, the letter, the walk.

The historical one. La Romantiko is Romanticism, the movement that ran through European art and letters from roughly 1790 to 1850 and put feeling, nature and the individual above the previous century's rules. Romantika poezio in the second example means poetry of that movement, not poetry about love, and the ambiguity is exactly as annoying in Esperanto as in English. The movement matters to this course more than it might look: Esperanto's own literary tradition begins in its long tail, and the nineteenth-century enthusiasm for national languages and folk poetry is a direct ancestor of Zamenhof's project. See esperanta literaturo.

The third, disparaging sense is in the last example. To call somebody's view of village life tro romantika is to say it is pretty and false. English does this too, and the Esperanto works identically, which is a small mercy.

The adverb romantike and the noun romantikeco (romantic quality) both behave predictably. Romantikismo is available for the movement if you want to be unambiguous, and in careful writing it is the better choice.