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The term circumstellar envelope (CSE) is used for shell-shaped visible clouds surrounding stars, sometimes material expelled by the star in what could be called a period of extreme stellar wind. The term is often used for such clouds around pre-main-sequence stars, as well as for the material expelled by asymptotic giant branch (AGB) stars (that is called a planetary nebula if it has been made to glow through ionization by the star's ionizing radiation).
The term circumstellar medium (CSM) refers to material surrounding a star that is somewhat different than the surrounding interstellar medium (ISM). The term "CSM" could be used for the Sun, but the terms interplanetary medium (IPM), solar wind, and heliosphere are generally sufficient, and CSM is also usually used for material around AGB stars and pre-main-sequence stars, including their CSEs.