A chemical element, symbol Er, belonging to the lanthanide series, commonly used in lasers and fiber-optic communications.

Referring to the ability to become rigid or erect, often used in the context of erectile tissues or organs like the penis or clitoris.

A unit of work or energy in the centimeter-gram-second (CGS) system, equal to 10^-7 joules.

The gradual wearing away of the earth’s surface due to natural forces such as wind, water, and ice.

Describing something that is unpredictable or irregular in behavior, movement, or pattern.

Redness of the skin caused by increased blood flow, often a response to irritation, inflammation, or infection.

A shallow sea that covers part of the continental shelf, often in periods of high sea levels.

The part of a plant embryo located above the cotyledons, which becomes the shoot and stem of the plant.

The entire upper part of the skull, including the scalp, bones, and connective tissues.

A waxy coating on the surface of plant leaves and stems that helps reduce water loss and protect against pests and pathogens.