eta

Eta is the diminutive suffix -et- standing up and walking off as a word in its own right. The suffix is everywhere: domo gives dometo, ridi gives rideti, monto gives monteto. Once you hear it as a suffix, the standalone adjective needs no learning at all.

It is not quite malgranda. Malgranda is the plain measurement, not big. Eta carries a shade of slight, dainty or minor, which is why eta doloro works for a twinge but malgranda doloro sounds like you have measured it.