КРУГ _|_ A CIRCLE / KRUG [kruk]    

Hint with an alternative definition: it is a circle figure, like a gyre, ring, disk, circus, racetrack, round crag (on a map)

Hint with composition: crook + crook = croog, the whole circle, k + k = g

Hints with translation + consonant words (by sounds or letters): group or range of currants (or any round objects) / a good guru figure (no angle) or crude + good = figure with no distortion

Russian pro-tip: фигура упругая без углов (углы крушили) / круг из рук друзей

Mental visualization: two fingers hold a pencil (K) and draw a circle (P), which is then checked by measuring tools (УГ)