| ad hoc(expression, free, casual, unplanned, unrehearsed) |
| ad libitum(expression, idiom, informal, unplanned, extemporize) |
| apace |
| at once(expression, idiom, instantaneity, earliness) |
| at short notice(expression, idiom, earliness) |
| autoschediastic(free, casual, impulsive, spontaneous, unprepared) |
| break loose(expression, adjective, simple, natural, casual) |
| briefly |
| by ear(expression, free, casual, impulsive, unrehearsed) |
| cadenza |
| coincidental |
| colloquial(adjective, simple, easy, plain, straightforward) |
| congenial(adjective, simple, easy, plain, straightforward) |
| democratic(adjective, simple, easy, plain, straightforward) |
| directly |
| down(adjective, simple, natural, casual, impulsive) |
| down home(expression, adjective, simple, plain, straightforward) |
| early(occasion, instantaneity) |
| everyday(adjective, simple, easy, plain, straightforward) |
| expedient(free, casual, impulsive, spontaneous, unprepared) |