Definitions from Wiktionary ( )

▸ adjective:  Not crooked, curly, or bent; having a constant direction throughout its length.
▸ adjective:  (of a path, trajectory, etc.) Direct, undeviating.
▸ adjective:  Perfectly horizontal or vertical; not diagonal or oblique.
▸ adjective:  (cricket) Describing the bat as held so as not to incline to either side; on, or near a line running between the two wickets.
▸ adjective:  (engineering, of an internal-combustion engine) Having all cylinders in a single straight line; in-line.
▸ adjective:  Direct in communication; unevasive, straightforward.
▸ adjective:  Free from dishonesty; honest, law-abiding.
▸ adjective:  Serious rather than comedic.
▸ adjective:  In proper order; as it should be.
▸ adjective:  In a row, in unbroken sequence; consecutive.
▸ adjective:  (tennis) Describing the sets in a match of which the winner did not lose a single set.
▸ adjective:  (US, politics) Making no exceptions or deviations in one's support of the organization and candidates of a political party.
▸ adjective:  (US, politics) Containing the names of all the regularly nominated candidates of a single party and no others.
▸ adjective:  (colloquial) Conventional; mainstream; socially acceptable.
▸ adjective:  (colloquial) Heterosexual.
▸ adjective:  (colloquial, of a romantic or sexual relation) Occurring between people of opposite sex (sometimes, but not always, specifically between heterosexual people).
▸ adjective:  (slang, sex work) Related to conventional sexual intercourse.
▸ adjective:  (colloquial) Not using alcohol, drugs, etc.
▸ adjective:  (fashion) Not plus size; thin.
▸ adjective:  (rare, now chiefly religion) Strait; narrow.
▸ adjective:  (obsolete) Stretched out; fully extended.
▸ adjective:  (slang) Thorough; utter; unqualified.
▸ adjective:  Of spirits: undiluted, unmixed; neat.
▸ adjective:  (telegraphy, historical, of a telegram) Sent at a full rate for immediate delivery; being a fast telegram.
▸ adjective:  (sciences, mathematics) Concerning the property allowing the parallel transport of vectors along a course that keeps tangent vectors remain as such throughout that course (a course which is straight, a straight curve, is a geodesic).
▸ adjective:  (informal, of a person) OK, all right, fine; in a good state or situation.
▸ adjective:  (informal, of people, reciprocal) On good terms.
▸ adverb:  Of a direction relative to the subject, precisely; as if following a direct line.
▸ adverb:  Directly; without pause, delay or detour.
▸ adverb:  Continuously; without interruption or pause.
▸ adverb:  Of speech or information, without prevarication or holding back; directly; straightforwardly; plainly.
▸ noun:  Something that is not crooked or bent such as a part of a road or track.
▸ noun:  (poker) Five cards in sequence.
▸ noun:  (colloquial) A heterosexual.
▸ noun:  (slang) A normal person; someone in mainstream society.
▸ noun:  (slang) A cigarette, particularly one containing tobacco instead of marijuana.
▸ noun:  A chiropractor who relies solely on spinal adjustment, with no other treatments.
▸ noun:  A cat that has straight ears despite belonging to a breed that often has folded ears.
▸ verb:  (transitive) To straighten.
▸ noun:  A surname.

---

▸ Word origin

▸ Words similar to straight
▸ Usage examples for straight

▸ Idioms related to straight
▸ Wikipedia articles (New!)
▸ Popular adjectives describing straight
▸ Popular nouns described by straight
▸ Words that often appear near straight
▸ Rhymes of straight

▸ Invented words related to straight