Etymology: Middle English streght, straight, from past participle of strecchen to stretch — more at stretch
Date: 14th century
1 a: free from curves, bends, angles, or irregularities <straight hair><straight timber>b: generated by a point moving continuously in the same direction and expressed by a linear equation <a straight line><the straight segment of a curve> 2 a: lying along or holding to a direct or proper course or method <a straight thinker>b:candid, frank<a straight answer>c: coming directly from a trustworthy source <a straight tip on the horses>d (1): having the elements in an order <the straight sequence of events>(2):consecutive<12 straight days>e: having the cylinders arranged in a single straight line <a straight 8-cylinder engine>f:plumb, vertical<the picture isn't quite straight> 3 a: exhibiting honesty and fairness <straight dealing>b: properly ordered or arranged <set the kitchen straight><set us straight on that issue>; also:correct<get the facts straight>c: free from extraneous matter :unmixed<straight whiskey>d: marked by no exceptions or deviations in support of a principle or party <votes a straight Democratic ticket>e: having a fixed price for each regardless of the number sold f: not deviating from an indicated pattern <writes straight humor><a straight-A student>g (1): exhibiting no deviation from what is established or accepted as usual, normal, or proper :conventional; also:square 5f (2): not using or under the influence of drugs or alcohol h:heterosexual 4: being the only form of remuneration <on straight commission>