SUBTLE

insidious, pernicious, subtle

(adjective) working or spreading in a hidden and usually injurious way; “glaucoma is an insidious disease”; “a subtle poison”

elusive, subtle

(adjective) difficult to detect or grasp by the mind or analyze; “his whole attitude had undergone a subtle change”; “a subtle difference”; “that elusive thing the soul”

subtle

(adjective) able to make fine distinctions; “a subtle mind”

Source: WordNet® 3.1

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Etymology

Adjective

subtle (comparative subtler or more subtle, superlative subtlest or most subtle)

Hard to grasp; not obvious or easily understood; barely noticeable.

Antonym: simple

(of a thing) Cleverly contrived.

(of a person or animal) Cunning, skillful.

Synonyms: crafty, cunning, skillful

Insidious.

Synonyms: deceptive, malicious

Tenuous; rarefied; of low density or thin consistency.

(obsolete) Refined; exquisite.

Anagrams

• bluest, bluets, bustle, butles, sublet

Source: Wiktionary

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Sub"tle, a. [Compar. Subtler; superl. Subtlest.] Etym: [OE. sotil, subtil, OF. soutil, later subtil, F. subtil, L. subtilis; probably, originally, woven fine, and fr. sub under + tela a web, fr. texere to weave. See Text, and cf. Subtile.]

1. Sly in design; artful; cunning; insinuating; subtile; -- applied to persons; as, a subtle foe. "A subtle traitor." Shak.

2. Cunningly devised; crafty; treacherous; as, a subtle stratagem.

3. Characterized by refinement and niceness in drawing distinctions; nicely discriminating; -- said of persons; as, a subtle logician; refined; tenuous; sinuous; insinuating; hence, penetrative or pervasive; -- said of the mind; its faculties, or its operations; as, a subtle intellect; a subtle imagination; a subtle process of thought; also, difficult of apprehension; elusive. Things remote from use, obscure and subtle. Milton.

4. Smooth and deceptive. [Obs.] Like to a bowl upon a subtle ground [bowling ground]. Shak.

Syn.

– Artful; crafty; cunning; shrewd; sly; wily. Subtle is the most comprehensive of these epithets and implies the finest intellectual quality. See Shrewd, and Cunning.

Source: Webster’s Unabridged Dictionary 1913 Edition

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