Herbs or subshrubs [shrubs or, rarely, lianas or trees], annual, biennial, or perennial; usually terrestrial, rarely submerged aquatics; with pungent watery juice; scapose or not; pubescent or glabrous, usually without papillae or tubercles (multicellular glandular papillae or tubercles present in Bunias, Chorispora, and Parrya); taprooted or rhizomatous (rarely stoloniferous), caudex simple or branched, sometimes woody, rhizomes slender or thick. Trichomes unicellular, simple, stalked, or sessile; forked, stellate, dendritic, malpighiaceous (medifixed, 2-fid, appressed), or peltate and scalelike, eglandular. Stems (absent in Idahoa, sometimes Leavenworthia) usually erect, sometimes ascending, descending, prostrate, decumbent, or procumbent; branched or unbranched. Leaves (sometimes persistent) cauline usually present, basal present or not (sometimes rhizomal present in Cardamine), rosulate or not, usually alternate (sometimes opposite or whorled in Cardamine angustata, C. concatenata, and C. diphylla and in Lunaria annua; sometimes subopposite in C. dissecta and C. maxima and in Draba ogilviensis), usually simple, rarely trifoliolate or pinnately, palmately, or bipinnately compound; stipules absent [with tiny, stipulelike glands at base of petioles and pedicels]; petiolate, sessile, or subsessile (sessile auriculate or not, sometimes amplexicaul); blade margins entire, dentate, crenate, sinuate, repand, or dissected. Inflorescences terminal, usually racemose (racemes often corymbose or paniculate) or flowers solitary on pedicels from axils of rosette leaves; bracts usually absent, sometimes present. Pedicels present (persistent or caducous [rarely geotropic]). Flowers bisexual [unisexual], usually actinomorphic (zygomorphic in Iberis, sometimes in Pennellia, Streptanthus, and Teesdalia); perianth and androecium hypogynous; sepals usually caducous, rarely persistent, 4, in 2 decussate pairs (1 pair lateral, 1 median), distinct [connate], not saccate or lateral (inner) pair (or, rarely, both pairs) saccate, forming tubular, campanulate, or urceolate calyx; petals 4, alternate with sepals, usually cruciform, rarely in abaxial and adaxial pairs, rarely rudimentary or absent, claw differentiated or not from blade, blade sometimes reduced and much smaller than well-developed claw, basally unappendaged, or, rarely, appendaged, margins entire or emarginate to 2-fid, rarely pinnatifid [fimbriate or filiform]; stamens (2 or 4) 6 [8–24], in 2 whorls, usually tetradynamous (lateral outer pair shorter than median inner 2 pairs), rarely equal in length or in 3 pairs of unequal length; filaments (slender, sometimes winged, appendaged, or toothed): median pairs usually distinct, rarely connate; anthers dithecal, dehiscing by longitudinal slits, pollen grains 3(–11)-colpate, trinucleate; nectar glands receptacular, variable in number, shape, size, and disposition around filament base, always present opposite bases of lateral filaments, median glands present or absent; disc absent; pistil 1, 2-carpellate; ovary 2-locular with false septum connecting 2 placentae, rarely 1-locular and eseptate, placentation usually parietal, rarely apical; gynophore usually absent; style 1, persistent [caducous], sometimes obsolete or absent; stigma capitate or conical, entire or 2-lobed, lobes spreading or connivent, sometimes decurrent, distinct or connate, rarely elongated into horns or spines; ovules 1–300 per ovary, anatropous or campylotropous, bitegmic, usually crassinucellate, rarely tenuinucellate. Fruits usually capsular, usually 2-valved ((3 or) 4(–6) in Rorippa barbareifolia, (2 or) 4 in Tropidocarpum capparideum), termed siliques if length 3+ times width, or silicles if length less than 3 times width, sometimes nutletlike, lomentaceous, samaroid, or schizocarpic and [with] without a carpophore carrying the 1-seeded mericarp, dehiscent or indehiscent, segmented or not, torulose or smooth, terete, angled, or flat, often latiseptate (flattened parallel to septum) or angustiseptate (flattened at right angle to septum); gynophore usually absent, sometimes distinct; valves each not or obscurely veined, or prominently 1–7-veined, usually dehiscing acropetally, rarely basipetally, sometimes spirally or circinately coiled, glabrous or pubescent [spiny or glochidiate]; replum (persistent placenta) rounded, flattened, or indistinct (obsolete in Crambe, often perforate in Thysanocarpus); septum complete, perforated, reduced to a rim, or absent (obsolete in Crambe and Thysanocarpus, not differentiated from replum in Raphanus), sometimes with a midvein or anastomosing veins. Seeds usually yellow or brown, rarely black or white, flattened or plump, winged or not, or narrowly margined, ovoid, oblong, globose, or ovate, usually uniseriate or biseriate, sometimes aseriate, per locule, mucilaginous or not when wetted; embryo usually strongly curved, rarely straight with tiny radicle; cotyledons entire, emarginate, 3[2]-fid to base, orientation to radicle: incumbent (embryo notorrhizal: radicle lying along back of 1 cotyledon), accumbent (embryo pleurorrhizal: radicle applied to margins of both cotyledons), conduplicate (embryo orthoplocal: cotyledons folded longitudinally around radicle), or spirally coiled (embryo spirolobal) [twice transversely folded (embryo diplecolobal)]; endosperm absent (germination epigeal).

(Flora of North America)