Chinta (Sanskrit: चिन्ता) in Hindu philosophy refers to mentation i.e. mental activity, especially thinking.
The word, Chintā (चिन्ता), is derived from the root – चिन्त् meaning - to think, consider, reflect, ponder over; and by itself means – thinking, thought, sad or sorrowful thought, reflection, consideration, anxiety
Chintā is one of thirty-three Vyabhichāri bhavas, the transient feelings which rise irregularly and support the permanent basic sentiments, because of their fleeting nature they are also called sanchāri bhavas.Manas, which is the ordinary mental equipment of the individual, is the perceiving and arranging mind. In Samkhya system it refers to the personal organ of thought, not diffused like theātman but localized in the individual. Manas has its own illumination (chetas) which gives man awareness or consciousness (chetna), faculties of perception (pratyaksha), thought (chintā), imagination (kalpanā) and volition (praytana). Chintā is the faculty whereby the current of thought dwells, thinks and contemplates upon the subject so recalled by Samarnam (memory), and previously known and determined by buddhi (intellect)
Rishi Shant Vaikhānsa of the Rig Veda (IX.66.25) in a mantra addressed to Soma tells us that
when the material darkness is dispelled by the powerful purifying (पवमानस्य) light emanating from the divine source, coinciding therewith is also the destruction of the darkness of the mind (जङ्घ्नतः) (which darkness is ignorance), then that light (जीराः) (the bright divine source) which is Brahman (अजिराशोचिषः) is seen which delivers the yogins beyond all (imaginable) folds (barriers) of existence, which existence with reference to the body is gross but is subtle with reference to the mind. The epithet – Soma as the ever glowing one, is used with regard to Agni, Aditya and Brahman.
Sankara in his Vivekachudamani (Sloka 539) uses the term – चिन्ताशून्यम् (chintashoonyam) as meaning without anxiety or worry (chinta here means anxiety). Chinmayananda Saraswati explains that it refers to the man of perfection to whom no thought comes to mind so as to disturb and destroy him because worry cannot reach him who refuses to worry.