ślakṣṇa: what the term means and how it is translated

ślakṣṇa श्लक्ष्ण is an Ayurvedic technical term. It is rendered into English in 6 different ways, which is the reason this page exists: the renderings do not agree, and the difference between them changes what the term is taken to mean.

Identification
Transliteration	ślakṣṇa
Devanagari	श्लक्ष्ण
Also written	slakshna, shlakshna, ślakṣṇaḥ, slakshma (Kaviratna's spelling in a footnote)
Category, as gathered	dravyaguna-3
Grouped here under	Pharmacology and the action of substances
Classical citations	4
Citations checked	2026-10-07

How it is translated, and whether the translation holds

Each rendering is given with the source that uses it. The assessment is ours.

Smoothness, slipperiness

WHO International Standard Terminologies on Ayurveda (2022), PDF mirror · ITA-1.9.4.2.10 description 'The quality of a substance which is responsible for smoothness.' ślakṣṇaḥ · comparator

'slipperiness' is WHO's addition; the description uses only 'smoothness'.

Reproduced unaltered and attributed from the WHO International Standard Terminologies on Ayurveda, which is what that licence permits. It is deliberately absent from the downloadable dataset, which is offered under CC BY 4.0 and invites the modification a NoDerivs licence forbids.

smooth

Charaka Samhita tr. A. C. Kaviratna, public domain · Su.22 his 11 bṛṁhaṇa list '...mild stable, and smooth'; Su.26 his 26 ākāśa objects 'mild, light, subtile, smooth'; Su.22 footnote 'Khara in Slakshma' (translator's note) · public-domain translation

Consistent 'smooth'; positional match to श्लक्ष्ण in both Sanskrit lists.

Humidity

Sushruta Samhita tr. K. L. Bhishagratna, public domain (archive.org OCR vol. 1 p. 568) · Su.Su.46 guna-karma: 'Humidity is like sliminess. Roughness is like absorption.' · public-domain translation

Positional match to श्लक्ष्णः पिच्छिलवज्ज्ञेयः कर्कशो विशदो यथा (46.521). 'Humidity' for ślakṣṇa is doctrinally odd and should be treated as a translator's error.

smooth (Akashiyam list)

Sushruta Samhita tr. K. L. Bhishagratna, public domain, via wisdomlib · Su.Su.41: 'A thing or substance, which is smooth, unctuous, and is subtle in its nature, soft or pliant in its consistency...is called a substance of the dominant principle of sky (Akashiyam)' · public-domain translation

Word-to-word mapping to a Sanskrit Su.41 not established, but 'smooth' heads the list as ślakṣṇa does in Charaka's ākāśa list.

Shlakshna (smooth) / Slakshna

Mithun & Singh, IJHSR 2026 review (DOI 10.52403/ijhsr.20260119) · 'Shlakshna-Khara (smooth-rough)'; 'Slakshna Guna imparts smoothness, lubrication, and aids in healing' · modern literature

Textbook rendering; the review itself uses two spellings.

smoothness

easyayurveda.com Su.Su.46 translation (Hebbar), modern, in copyright · 'Slaksna means smoothness. This quality is similar to Pichchila – sliminess.' · modern web textbook

Recorded as a rendering only.

The classical passages

Each citation gives its address so a reader can check it in a printed edition, our account of what the passage establishes, and the result of reading it against its source.

Charaka SamhitaSutrasthana 22:Standard 22.13 (second half) to 22.14 (first half); Kaviratna prints 11 · checked against the source

Such things as are heavy, cooling, soft, exceedingly oily, gross, slimy, mild stable, and smooth, are generally said to be Vringhana.

tr. A. C. Kaviratna · source

Ślakṣṇa ('smooth') closes the bṛṁhaṇa quality list. Sanskrit as retrieved: गुरु शीतं मृदु स्निग्धं बहलं स्थूलपिच्छिलम्||१३|| प्रायो मन्दं स्थिरं श्लक्ष्णं द्रव्यं बृंहणमुच्यते| (https://www.carakasamhitaonline.com/index.php/Langhanabrimhaniya_Adhyaya).

Charaka SamhitaSutrasthana 26:Standard 26.11 (ākāśa clause); Kaviratna prints 26 · checked against the source

Those that are mild, light, subtile, smooth, and largely endued with the property of sound, are regarded as having Ether for their essence.

tr. A. C. Kaviratna · source

Ślakṣṇa as a quality of ākāśa-dominant substances (alongside mṛdu, laghu, sūkṣma, śabda). Sanskrit as retrieved: मृदुलघुसूक्ष्मश्लक्ष्णशब्दगुणबहुलान्याकाशात्मकानि (within ||११||, https://www.carakasamhitaonline.com/index.php/Atreyabhadrakapyiya_Adhyaya).

Charaka SamhitaSutrasthana 25:Standard 25.36 (prose) · checked against the source

विंशतिगुणः, गुरुलघुशीतोष्णस्निग्धरूक्षमन्दतीक्ष्णस्थिरसरमृदुकठिनविशदपिच्छिलश्लक्ष्णखरसूक्ष्मस्थूलसान्द्रद्रवानुगमात्

tr. none (Sanskrit only) · source

Ślakṣṇa paired with khara in Charaka's twenty.

Sushruta SamhitaSutrasthana 46:Sushruta Sutrasthana 41.4, fifth sub-clause ((५) within ॥४॥, the ākāśīya classification); Bhishagratna prints no verse number, vol. 1 pp. 376-377 · checked against the source

श्लक्ष्णसूक्ष्ममृदुव्यवायिविशदविविक्तमव्यक्तरसं शब्दबहुलमाकाशीयं, तन्मार्दवशौषिर्यलाघवकरमिति ॥ (५) ॥ ४ ॥

tr. K. L. Bhishagratna · source

Ślakṣṇa heads Sushruta's list of qualities marking ākāśa-dominant substances (Su.Su. 41.4, fifth clause: ślakṣṇa, sūkṣma, mṛdu, vyavāyi, viśada, vivikta, avyaktarasa, śabdabahula), paralleling Charaka's ākāśa list at Ca.Su. 26.11. Ḍalhaṇa glosses ślakṣṇaṃ masṛṇam. Bhishagratna's 'smooth' at the head of his Akashiyam list therefore does render ślakṣṇa; his following 'unctuous' answers to nothing in the Sanskrit and must not be read as snigdha, which belongs to the āpya clause of the same sūtra.

Not to be confused with

khara / karkaśa: Paired opposite (Charaka uses khara, Ca.Su.25.36; Sushruta uses karkaśa, Su.Su.46.521). Kaviratna's footnote: 'Khara in Slakshma'.
picchila: Su.Su.46.521 says ślakṣṇa is 'picchilavat' (like slimy), similar, not identical; WHO keeps separate headwords (ITA-1.9.4.2.10 vs.21).
snigdha: Unctuousness; WHO's snigdha definition includes 'smoothness', which invites confusion. Snigdha is oily; ślakṣṇa is smooth to touch and may be dry (ākāśa substances are ślakṣṇa but not snigdha in Ca.Su.26.11).
mṛdu: Softness, a separate guna that co-occurs in the ākāśa list.
sūkṣma: Subtlety, also co-occurring in the ākāśa list and the bṛṁhaṇa list.

Renderings that do not hold

Humidity. Bhishagratna's rendering at Su.Su.46.521; ślakṣṇa has nothing to do with moisture. Probably a slip induced by the picchila comparison.
slippery / slimy. WHO's 'slipperiness' and Sushruta's 'like picchila' push towards sliminess; Charaka's ākāśa list shows ślakṣṇa can be dry smoothness.
soft. Confuses ślakṣṇa with mṛdu; both appear separately in Ca.Su.26.11.

Open questions

Recorded rather than resolved. Each one is something this entry cannot currently settle.

Whether 'smooth' in Bhishagratna's Su.Su.41 Akashiyam list is ślakṣṇa in the Sanskrit (needs a Sanskrit Su.41).
Is Bhishagratna's 'Humidity' an OCR or typesetting error rather than his word? A human should check the printed page 568 of vol. 1.

How to cite this entry

Age Ayurveda Nighantu, ślakṣṇa, https://nighantu.ageayurveda.com/lexicon/shlakshna/, CC BY 4.0. The whole lexicon is downloadable from the index. Machine-readable source: Markdown. Data exported 2026-10-08.

Educational reference only. A term entry explains what a word means and how it has been translated. Nothing here is advice, and nothing here describes how any condition should be treated.