95dc162e_Glossary_of_Dance_Terms__m_Dance_Dictionary_from_Webref
Ah [Abbreviations] a
In the timing of dance steps and actions, an "a" represents only 1/4 beat. In a fast jive, a basic rock is danced "1, 2, 3/a, 4; 1/a, 2, The third step (count 3) is quick, only 3/4 of a beat, but the fourth step (the "a") really allows you to take only partial weight before you have to bounce off and into the fifth step (count 4). If an "&" is very quick (see below), then an "a" is very very quick.
Glossary of Dance Terms
Description Glossary of Terms and Abbreviations from BallroomDancers.com Dance Dictionary from Webref