C nictitans

Sensitive Sen"si*tive, a. [F. sensitif. See {Sense}.] 1. Having sense of feeling; possessing or exhibiting the capacity of receiving impressions from external objects; as, a sensitive soul. [1913 Webster]

2. Having quick and acute sensibility, either to the action of external objects, or to impressions upon the mind and feelings; highly susceptible; easily and acutely affected. [1913 Webster]

She was too sensitive to abuse and calumny. --Macaulay. [1913 Webster]

3. (a) (Mech.) Having a capacity of being easily affected or moved; as, a sensitive thermometer; sensitive scales. (b) (Chem. & Photog.) Readily affected or changed by certain appropriate agents; as, silver chloride or bromide, when in contact with certain organic substances, is extremely sensitive to actinic rays. [1913 Webster]

4. Serving to affect the sense; sensible. [R.] [1913 Webster]

A sensitive love of some sensitive objects. --Hammond. [1913 Webster]

5. Of or pertaining to sensation; depending on sensation; as, sensitive motions; sensitive muscular motions excited by irritation. --E. Darwin. [1913 Webster]

{Sensitive fern} (Bot.), an American fern ({Onoclea sensibilis}), the leaves of which, when plucked, show a slight tendency to fold together.

{Sensitive flame} (Physics), a gas flame so arranged that under a suitable adjustment of pressure it is exceedingly sensitive to sounds, being caused to roar, flare, or become suddenly shortened or extinguished, by slight sounds of the proper pitch.

{Sensitive joint vetch} (Bot.), an annual leguminous herb ({[AE]schynomene hispida}), with sensitive foliage.

{Sensitive paper}, paper prepared for photographic purpose by being rendered sensitive to the effect of light.

{Sensitive plant}. (Bot.) (a) A leguminous plant ({Mimosa pudica}, or {M. sensitiva}, and other allied species), the leaves of which close at the slightest touch. (b) Any plant showing motions after irritation, as the sensitive brier ({Schrankia}) of the Southern States, two common American species of Cassia ({C. nictitans}, and {C. Cham[ae]crista}), a kind of sorrel ({Oxalis sensitiva}), etc. [1913 Webster] -- {Sen"si*tive*ly}, adv. -- {Sen"si*tive*ness}, n. [1913 Webster]