the.com/oxalis

means A genus of plants with clover-like leaflets (often in threes or more) and five-petaled flowers, many species of which fold their leaflets at night or under stress and contain sour-tasting oxalic acid.

from From Greek 'oxys,' meaning sharp or sour — the same root that gives us 'oxygen' (literally 'sharp-producer,' coined for the sour taste of acids). 'Oxalis' passed through Latin as the name for sorrel-like sour plants before becoming the botanical genus name, a fitting lineage for a leaf that bites back.