1 one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock).
2 An abstract place usually conceived as having depth.
Noun. 1. stratum-one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock). organism, being-a living thing that has (or can develop) the ability to act or function independently. Any of the regions of the atmosphere, such as the troposphere, that occur as layers. 4. Biology A layer of tissue: the epithelial stratum. 5. A level of society composed of people with similar social, cultural, or economic status. The stratum corneum (Latin for 'horny layer') is the outermost layer of the epidermis, consisting of dead cells (corneocytes). This layer is composed of 15-20 layers of flattened cells with no nuclei and cell organelles.  The stratum corneum, or the skin barrier, acts as our first line of defense against the external environment. It is a compact layer of cells and lipids that has two critical functions: it protects our bodies from bacteria, UV damage and other assaults; and prevents natural moisture from escaping, to keep skin hydrated.  A server that is directly connected to a stratum-0 device is called a stratum-1 server. This includes all time servers with built-in stratum-0 devices, such as the EndRun Time Servers, and also those with direct links to stratum-0 devices such as over an RS-232 connection or via an IRIG-B time code. Thus, a stratum-2 server gets its time via NTP packet requests from a stratum-1 server. A stratum-3 server gets its time via NTP packet requests from a stratum-2 server, and so on. As you progress through different strata there are network delays involved that reduce the accuracy of the NTP server in relation to UTC. • STRATUM (noun). The noun STRATUM has 2 senses: 1. one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock). 2. an abstract place usually conceived as having depth. Familiarity information: STRATUM used as a noun is rare. stratum lucidum-the layer of epidermis immediately under the stratum corneum in the skin of the palms and soles. stratum granulosum-the layer of epidermis just under the stratum corneum or (on the palms and soles) just under the stratum lucidum; contains cells (with visible granules) that die and move to the surface. malpighian layer, rete Malpighii, stratum basale, stratum germinativum-the innermost layer of the epidermis. Any of the regions of the atmosphere, such as the troposphere, that occur as layers. 4. Biology A layer of tissue: the epithelial stratum. 5. A level of society composed of people with similar social, cultural, or economic status. The stratum basale (basal layer, sometimes referred to as stratum germinativum) is the deepest layer of the five epidermis layers, which is the outer covering of skin in mammals. The stratum basale is primarily made up of basal keratinocyte stem cells, which can be considered the stem cells of the epidermis. Princeton's WordNet (0.00 / 0 votes) Rate this definition: stratum (noun). one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock). Stratum (noun). a bed of earth or rock of one kind, formed by natural causes, and consisting usually of a series of layers, which form a rock as it lies between beds of other kinds. Also used figuratively. Stratum (noun). a bed or layer artificially made; a course. stratum lucidum (the layer of epidermis immediately under the stratum corneum in the skin of the palms and soles). corneum; horny layer; stratum corneum (the outermost layer of the epidermis consisting of dead cells that slough off). bed ((geology) a stratum of rock (especially sedimentary rock)). 1. one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock). 2. an abstract place usually conceived as having depth. Familiarity information: STRATUM used as a noun is rare. The noun STRATUM GRANULOSUM has 1 sense: 1. the layer of epidermis just under the stratum corneum or (on the palms and soles) just under the stratum lucidum; contains cells (with visible granules) that die and move to the surface. Familiarity information: STRATUM GRANULOSUM used as a noun is very rare. Dictionary entry details. • STRATUM GRANULOSUM (noun). 
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