штуковина

1) General subject: doing, doodad, gismo, hickey (вместо забытого названия какого-л. предмета, приспособления), widget, thingie (A thing you don't know the exact word for), twiddly bit (used to talk about small part of an object without naming it), doofah (употребляется вместо названия, когда говорящий не может его вспомнить), thingamabob, thingamajig, thingumajig, thingummy

2) Colloquial: contraption, doings, doodah, doohickey, gizmo (any object whose name one does not know), hootenanny, whachamacallit (хреновина, или "мужик", "тетка", "баба" и т.п. - an object or person whose name one does not know or cannot recall), oojamaflip

3) Jargon: kadigin-thingamajig, kajody, wingdoodle, thumadoodle, whatchamacallit, gadget, gismol, whing-ding, whingding, wing-ding, wingding

4) American English: do-jigger, domajig, doosenwhacker, doowacky, thingy