lumen

views updated May 11 2018

lu·men1 / ˈloōmən/ (abbr.: lm) • n. Physics the SI unit of luminous flux, equal to the amount of light emitted per second in a unit solid angle of one steradian from a uniform source of one candela.lu·men2 • n. (pl. -mi·na / -mənə/ ) Anat. the central cavity of a tubular or other hollow structure in an organism or cell.DERIVATIVES: lu·mi·nal / -mənl/ adj.

lumen

views updated May 21 2018

lumen
1. The space enclosed by a vessel, duct, or other tubular or saclike organ. The central cavity of blood vessels and of the digestive tract are examples.

2. Symbol lm. The SI unit of luminous flux equal to the flux emitted by a uniform point source of 1 candela in a solid angle of 1 steradian.

lumen

views updated Jun 08 2018

lumen (symbol lm) SI unit measuring the amount of light in an area for one second. The light emits in a unit solid angle (one steradian) from a source of unit intensity (one candela).

lumen

views updated May 18 2018

lumen A space enclosed by cell walls. Compare LACUNA.

lumen

views updated Jun 11 2018

lumen (loo-min) n.
1. the space within a tubular or saclike part.

2. the SI unit of luminous flux. Symbol: lm.

lumen

views updated Jun 11 2018

lumen A cavity inside a cell or bodily structure.