These words refer to an ability for making fine distinctions or to the possession of qualities that set the subject apart from others of its kind. Discriminate pertains mostly to someone perceiving and evaluating differences among very similar things: discriminating the real antique from the faked-up fraud; the connoisseur who can discriminate among several equally fine wines. Discern relates closely to discriminate but is somewhat pore general in stressing any intense or accurate perception without necessarily implying that it is a sorting out of closely related items: discerning clearly the faint trail of clues that led to the identity of the murderer.

Distinguish , by contrast, can refer either to an ability of the perceiver or to the differences actually perceived. In the former case, it suggests the making of even finer distinctions than discriminate and making them among things even more closely resembling each other. The word, consequently, stresses the skill needed for the mere detection of differences and does not emphasize, like discriminate , aesthetic evaluation as a part of the process.

• She was unable to distinguish the grey shadow she made from all the other shadows in the garden; Anyone can learn to discriminate between a Goya and a Velásuez but only a real student of the period can distinguish their stylistic tendencies.

Distinguish , however, when it refers to characteristics of a thing perceived is quite the opposite; in this case it suggests drastically different and often superior qualities: amazing agility that distinguishes him from all other dancers.

Differentiate , in referring to qualities in something perceived, contrasts sharply with distinguish , suggesting slighter differences and one seldom the result of excellence.

• The yellows used to paint the sun were only faintly differentiated from the other yellows used throughout the whole sky; it took a sharp eye to distinguish one shade from the other.

Differentiate in the sense of making distinctions is most appropriate to a technical context: the entomologist who had differentiated sixty separate species of insects.