late 14c., "meaning, signification, interpretation" (especially of Holy Scripture); c. 1400, "the faculty of perception;" from Old French sens "one of the five senses; meaning; wit, understanding" (12c.) and directly from Latin sensus "perception, feeling, undertaking, meaning," from sentire "perceive, feel, know."

This probably is a figurative use of a literal meaning "find one's way," or "go mentally." According to Watkins and others, this is from a PIE root *sent- "to go" (source also of Old High German sinnan "to go, travel, strive after, have in mind, perceive," German Sinn "sense, mind," Old English sið "way, journey," Old Irish set, Welsh hynt "way").

The application to any one of the external or outward senses (touch, sight, hearing, any special faculty of sensation connected with a bodily organ) in English is recorded from 1520s. They usually are reckoned as five; sometimes a "muscular sense" and "inner (common) sense" are added (perhaps to make the perfect seven), hence the old phrase the seven senses, sometimes meaning "consciousness in its totality." For the meaning "consciousness, mind generally," see senses.

The meaning "that which is wise, judicious, sensible, or intelligent" is from c. 1600. The meaning "capacity for perception and appreciation" also is from c. 1600 (as in sense of humor, attested by 1783, sense of shame, 1640s). The meaning "a vague consciousness or feeling" is from 1590s.

1827, a hybrid from hyper- "over, exceedingly, to excess" + sensitive. Related: Hypersensitivity; hypersensitiveness.

c. 1600, "having little or no reaction to what is perceived by one's senses," from in- (1) "not, opposite of" + sensitive. For sense, see insensate. From 1834 as "having little or no mental or moral sensitiveness;" meaning "without consideration for the feelings of others" attested by 1974. Related: Insensitively.

also over-sensitive, "excessively sensitive," by 1798, from over- + sensitive. Related: Oversensitively; oversensitiveness.

late 14c., "capable of sensation or feeling;" also "capable of being sensed or felt, perceptible to the senses," hence "perceptible to the mind, easily understood; logical, reasonable," from Old French sensible and directly from Late Latin sensibilis "having feeling: perceptible by the senses," from sensus, past participle of sentire "to perceive, feel" (see sense (n.)).

Of persons, from c. 1400 as "capable of mental perception, having good sense, clever, discerning;" by early 15c. as "aware, cognizant (of something)." Of actions, discourse, etc., "marked by or proceeding from (good) sense," 1650s. In reference to clothes, shoes, etc., "practical rather than fashionable," it is attested from 1855.

Other Middle English senses included "susceptible to injury or pain" (early 15c., common through 18c., now gone with sensitive); "worldly, temporal, outward" (c. 1400); "carnal, unspiritual" (early 15c., now gone with sensual). Related: Sensibleness.

"state of being sensitive" in any way, 1803, from sensitive + -ity. The specific meaning "delicacy of feeling, touchiness" is by 1851. Of mechanical devices by 1918. The psychological sensitivity training, meant to increase one's awareness of feelings and motives, is attested by 1954.

also sensitise, "render sensitive," 1856, in photography; see sensitive + -ize. Of persons from 1880. Related: Sensitized; sensitizer; sensitizing.