phrasal free from pain or discomfort, 2. free from restraint or formality , standing silently (as in a military formation) with the feet apart, the right foot in place, and one or both hands behind the body
AT EASE
Meaning of AT EASE in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012