Definition from Wiktionary, the free dictionary
- Not erect or perpendicular; neither parallel to, nor at right angles from, the base; slanting; inclined.
- It has a direction oblique to that of the former motion. - Cheyne.
- Not straightforward; indirect; obscure; hence, disingenuous; underhand; perverse; sinister.
- The love we bear our friends . . . Hath in it certain oblique ends. - Drayton.
- This mode of oblique research, when a more direct one is denied, we find to be the only one in our power. - De Quincey.
- Then would be closed the restless, oblique eye. / That looks for evil, like a treacherous spy. - Wordworth.
- Not direct in descent; not following the line of father and son; collateral.
- His natural affection in a direct line was strong, in an oblique but weak. - Baker.
- (botany, of leaves) Having the base of the blade asymmetrical, with one side larger or extending further than the other.
not erect or perpendicular; neither parallel to, nor at right angles from
not straightforward; indirect; obscure; hence, disingenuous; underhand; perverse; sinister
not direct in descent; not following the line of father and son; collateral
Derived terms 
terms derived from oblique (adj)
oblique (plural obliques)
- To deviate from a perpendicular line; to move in an oblique direction.
- Projecting his person towards it in a line which obliqued from the bottom of his spine. - Sir. W. Scott.
- (military) To march in a direction oblique to the line of the column or platoon; — formerly accomplished by oblique steps, now by direct steps, the men half-facing either to the right or left.
Borrowed from Latin obliquus.
oblique (masculine and feminine, plural obliques)
- first-person singular present indicative of obliquer
- third-person singular present indicative of obliquer
- first-person singular present subjunctive of obliquer
- third-person singular present subjunctive of obliquer
- second-person singular imperative of obliquer
- Feminine plural form of obliquo
- vocative masculine singular of oblīquus