An Etymological Dictionary of Astronomy and Astrophysics
English-French-Persian

Tending not to participate actively; not working or operating.

From L. passivus "submissive; capable of feeling or suffering," from passus, p.p. of pati "to experience, undergo, suffer."

Akâr "not working, not doing," from → a- negation prefix + kâr "work," varaint of kar, present stem of kardan "to do, to make" (Mid.Pers. kardan; O.Pers./Av. kar- "to do, make, build;" Av. kərənaoiti "he makes;" cf. Skt. kr- "to do, to make," krnoti "he makes, he does," karoti "he makes, he does," karma "act, deed;" PIE base k^wer- "to do, to make").

A cumulus cloud that is no longer dynamically connected with the atmospheric boundary layer via updrafts or downdrafts.

→ passive; → cloud.

An electronic component which contains no source of power, in contrast to active components.

→ passive; → component.

A galaxy lacking optical emission-line activity (e.g., [O II], Hα, [O III]) and showing only stellar absorption lines (e.g., the 4000 Å → calcium break, Mg I, Na I). Also called passively evolving galaxy.

→ passive; → galaxy.

An electronic system which emits no energy, and is not detectable.

→ passive; → system.

Same as → passive galaxy.

→ passive; → evolve; → galaxy.