Arecaceae

Fruit usually a berryberry:
an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
, drupedrupe:
(indehiscent drupe) a fleshy, indehiscent fruit with one more hard pits enclosing seeds, derived from single, superior, simple or compound ovary; (dehiscent drupe) a fruit with a dry or fibrous to fleshy or leathery outer husk that early to tardily breaks apart (or opens), exposing one or more nutlike pits enclosing the seeds
, or nutnut:
a fairly large, indehiscent, dry fruit with a thick and bony wall surrounding a single seed, derived from a single, simple or compound ovary
, 6–800 mm long, shape variable from hemisphericalhemispherical:
2D shape—shaped like half a sphere
to angularangular:
2D shape—having sides that meet at acute or obtuse angles  
, tereteterete:
approximately circular in cross section; width and thickness approximately equal
in transection, often stylestyle:
in a flower, the narrow and elongated part of the pistil between the stigma and the ovary; sometimes persisting in fruit
persistent, often beakedbeak:
a usually firm, terminal appendage, sometimes tapered
. BerriesBerry:
an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
one or sometimes 2–3(–10) seeded. Fruits are often simple, but aggregateaggregate:
fruit formed from a single flower with carpels several and distinct
fruits occur in several genera. Fruits sometimes with persistent sepalssepal:
a member of the outer envelope of a flower (calyx)
, petalspetal:
a member of the inner envelope of a flower (corolla)
, imbricated scales, and/or staminodal ring. Pericarp black, brown, green, white, blue, orange, red, or yellow, shinyshiny:
uniformly reflecting a high proportion of incident light at all angles
or dulldull:
reflecting only a low proportion of incident light, with no apparent sheen
, fleshy or indurateindurate:
texture—hardened or stony; yielding under strong pressure; not deformable without internal structural disruption
, glabrousglabrous:
without hairs
or pubescentpubescent:
surface relief—bearing hairs
, smooth, scaly, fibrousfibrous:
texture—long, flexible threads, thicker than hairs, that densely cover and obscure the surface
, wartywarty:
surface relief—distinct, rounded projections that are large relative to the fruit size; tuberculate, verrucose
, wrinkledwrinkled:
surface relief—shallow, irregular folds and furrows covering the surface; appearing overall though crumpled and then spread out
, or spinyspiny:
having slender, stiff, sharp projections oriented in the general plane of the structure
. Often the outer layers (epicarpepicarp:
outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with exocarp
and mesocarpmesocarp:
the middle layer of the pericarp, if divided into layers
) are shed early and only the endocarpendocarp:
the inner layer of the pericarp, if divided into layers
is present at dispersal. In fruits with differentiated endocarps, endocarps are thin (sometimes with operculaoperculum:
a dehiscent cap (or lid) of a seed or fruit that opens during germination or dehiscence
) to bonybony:
very hard and rather brittle, like bone
or thick and woodywoody:
texture—consisting mainly of indurate lignified tissues, characteristic of or resembling wood
(often with 1–3 pores). 

Seeds globoseglobose:
3D shape—more or less spherical
to kidney shapedkidney-shaped:
2D shape—broadly elongate and with one margin convex and the opposite side concave, each end bluntly rounded
, tereteterete:
approximately circular in cross section; width and thickness approximately equal
to plano-convexplano-convex:
2D or 3D shape—flat on one side, convex on the other
in transection, 3–50+ mm long, prominent operculaoperculum:
a dehiscent cap (or lid) of a seed or fruit that opens during germination or dehiscence
or micropylarmicropyle:
an opening in the integuments of an ovule usually acting as a passage for the pollen tube
plugs, and often with conspicuous raphe variable in shape. Hilum short or to the length of the seed, apicalapical:
at or pertaining to the end of the seed or fruit distal from its point of attachment (i.e., base)
, laterallateral:
(of embryo) embryo lies along the side of the seed, generally towards one end; of, at, or from the side; in grasses, can refer to the sides adjacent to the dorsal and ventral sides
, or basalbasal:
at or pertaining to the point of attachment; (of embryo) embryo occupies one end of the seed
, linearlinear:
(shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide
to circularcircular:
(of embryo) linear embryo is curved into an "O" shape
. Several genera have seeds with a sarcotestasarcotesta:
pulpy or fleshy outer layer of the seed coat, simulates aril
. Seed coat brown, shinyshiny:
uniformly reflecting a high proportion of incident light at all angles
, leatheryleathery:
texture—moderately thick, tough, and very pliable
or membranousmembranous:
texture—extremely thin, pliable, and fairly tough
, smooth or variously ornamented. 

Embryo well developed, cylindricalcylindrical:
3D shape—a cylinder, with parallel sides and a circular cross-section; tubular or rod-shaped
or conical, curvedcurved:
(of embryo) linear embryo is curved into an arch or horseshoe with the ends far apart
or straight, embedded in endosperm.

Endosperm copious, cartilaginouscartilaginous:
texture—firm, dense, tough, somewhat pliable, and resilient, like cartilage
or hard, homogenous or ruminateruminate:
testa or seed coat folded into the endosperm
.

*For keys to the subfamilies, tribes, and genera as well as images and illustrations representing these groups, see Dransfield et al. 2008Dransfield et al. 2008:
Dransfield J, Uhl NW, Asmussen CB, Baker W, Harley MM, and Lewis CE. 2008. Genera Palmarum: The Evolution and Classification of Palms. Royal Botanic Gardens, Kew, London UK. 732 pp. https://doi.org/10.34885/92. This book is publicly available. Or, for identifying commonly cultivated palms, see Identifying Commonly Cultivated Palms.