sage

The plant Salvia officinalis and savory spice produced from it; also planted for ornamental purposes.

Any plant in the genus Salvia.

Any of a number of plants such as sagebrush considered to be similar to Salvia officinalis, mostly because they are small shrubs and have gray foliage or are aromatic.

A very wise person or spiritual teacher; someone of gravity and wisdom, especially, a teacher venerable for years, and of sound judgment and prudence; a grave or stoic philosopher.

Wise.

(no longer used) Grave; serious; solemn.

(Internet) Word used in the email field of imageboards to prevent a bump of the post. Used as an option rather than a word in some imageboard software.

(Internet) The act of using the word or option sage in the email field or a checkbox of an imageboard when posting a reply.