ingenious

ingenious, ingenuous

These two words are distantly related and both have undergone a major shift in meaning. Ingenious came into English via French from a Latin source derived from ingenium ‘cleverness’; it originally meant ‘intellectual, talented’, but the meaning gradually weakened and its current sense is less complimentary and even depreciatory, ‘(of a person) clever, showing aptitude for devising curious devices’ and ‘(of a device or idea) cleverly contrived’:

• There were the ingenious hand-made toys, the shadow-puppets manipulated on sticks —H. Trevelyan, 1971

• I see…that some ingenious person…has videotaped my television series —Brian Aldiss, 1980

• The score ingeniously employs reeds, brass, percussion and lower strings, instruments that can be associated with power and oppressive darkness —MV Daily, AmE 2003 [OEC].

Ingenuous, by contrast, is derived from Latin ingenuus ‘freeborn’ and originally meant ‘befitting a free man, noble in character’, eventually weakening in sense to mean ‘open, frank, candid’:

• Getty arrived half an hour late with the ingenuous excuse that he had miscalculated how long it would take him to walk from the Ritz to Boodles Club in St James's Street —Art Newspaper, 1992

• She smiled ingenuously and the openness of her face seemed to ease his bad temper a little —S. Wood, 1993

• Akimov speaks with ingenuous enthusiasm about his commitment to unifying the company —Guardian, 2001.

The noun ingenuity was originally a derivative of ingenuous but was usurped by ingenious in the 16c, so that in current use ingenuity corresponds to ingenious, and ingenuousness corresponds to ingenuous. See also disingenuous.