| trial balloon | (n) a test of public opinion |
| trial balloon | (n) a balloon sent up to test air currents |
| バロンデッセ | [barondesse] (n) trial balloon (fre [Add to Longdo] |
| 観測気球 | [かんそくききゅう, kansokukikyuu] (n) (1) weather balloon; sounding balloon; (2) observation balloon; espionage balloon; spy balloon; (3) trial balloon [Add to Longdo] |