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

1) Lacking brightness, vividness, clearness, loudness, strength; feeble; exhausted.
2) To lose consciousness temporarily; to lose brightness (Dictionary.com).

From O.Fr. faint, feint "false, deceitful; sham, artificial; weak, faint, lazy," p.p. of feindre "hesitate, falter, show weakness," from L. fingere "to touch, handle; change."

Tâm, from Pers. tâm "feeble, fragile, weak," ultimately from Proto-Ir. *tamH- "to faint, be tired;" cf. Khotanese ttāmā "fatigue;" Parthian t'm'dg "fainted, choking;" Gilak (Langarudi) tâmâ, tâm "silent;" PIE base *temH- "to faint, to be dark;" tâmidan, infinitive from tâm.
Nazâr, from Mid.Pers. nizâr "weak, feeble" (variant zâr), zarmân "old man, deterioration;" Av. zairina- "exhausting, slackening," zaurura- "weak through old age, decrepit;" cf. Skt. jára- "wearing out, exhaustion," jaranā- "old, decayed," jarimán- "weakness through old age," Gk. geron "old man," L. granum "grain;" PIE base *ger- "wear away."
Kamtâb, from kam "little, few; deficient, wanting; scarce," from Mid.Pers. kam "little, small, few," O.Pers./Av. kamna- "small, few" + tâb "light; heat, warmth; illuminating," from tâbidan, tâftan "to shine," tafsidan "to become hot;" Av. tāp-, taf- "to warm up, heat," tafsat "became hot," tāpaiieiti "to create warmth;" cf. Skt. tap- "to spoil, injure, damage; to suffer; to heat, be/become hot," tapati "burns;" L. tepere "to be warm," tepidus "warm;" PIE base *tep- "warm."
Kamnur, from kam, as above, + nur, → light.

The contradiction between a colder Sun (about 30% less luminous) some 4 billion years ago, as predicted by models, and the warm ancient Terrestrial and Martian climates derived from geological evidence.

→ faint; → early; → sun; → paradox.

For unaided eye, a star of visual magnitude around 5-6. Otherwise, on an image, a star that has a lesser brightness compared to others of the same field.

→ faint; → star.