balanci

The false family, and it is a big one. Balanci looks as though it belongs with balo, a ball in the dancing sense, and balono, a balloon. It does not. Bal- is from French bal, from Late Latin ballare, to dance. Balon- is from Italian ballone, a big ball. Balanc- is from Latin bilanx, a two-panned weighing scale, and has nothing whatever to do with dancing or with spheres. Three roots that start with the same three letters and share no ancestor at all. Nor is there a suffix -anc- in Esperanto to explain the rest of it - the root is balanc- entire.

Transitive, which trips people. You balancas something: a cradle, your head, a boat. For the thing doing it by itself you need -iĝ-: la ŝipo balanciĝis, the ship rocked. And the derivation everybody eventually wants is balancilo with the tool suffix - a swing in a playground, or a see-saw, which is one of those words that makes the affix system feel like a cheat code. Balanco is a balance in the accounting sense.

Three neighbours worth separating. Luli is specifically to lull a baby, and it carries the singing with it - lulilo is the cradle you met eighty ranks ago. Svingi is a bigger, more deliberate motion: to brandish, to wave something about. Ŝanceliĝi is unsteady and involuntary, the totter of somebody about to fall. Balanci is even, controlled and regular - the motion of a pendulum, which is a pendolo, and which is the same idea as pendi, to hang.