'At a start' definitions:

Definition of 'At a start'

From: GCIDE

Start \Start\, n.
1. The act of starting; a sudden spring, leap, or motion, caused by surprise, fear, pain, or the like; any sudden motion, or beginning of motion. [1913 Webster]
The fright awakened Arcite with a start. --Dryden. [1913 Webster]
2. A convulsive motion, twitch, or spasm; a spasmodic effort. [1913 Webster]
For she did speak in starts distractedly. --Shak. [1913 Webster]
Nature does nothing by starts and leaps, or in a hurry. --L'Estrange. [1913 Webster]
3. A sudden, unexpected movement; a sudden and capricious impulse; a sally; as, starts of fancy. [1913 Webster]
To check the starts and sallies of the soul. --Addison. [1913 Webster]
4. The beginning, as of a journey or a course of action; first motion from a place; act of setting out; the outset; -- opposed to finish. [1913 Webster]
The start of first performance is all. --Bacon. [1913 Webster]
I see you stand like greyhounds in the slips, Straining upon the start. --Shak. [1913 Webster]
At a start, at once; in an instant. [Obs.] [1913 Webster]
At a start he was betwixt them two. --Chaucer. [1913 Webster]
To get the start, or To have the start, to begin before another; to gain or have the advantage in a similar undertaking; -- usually with of. "Get the start of the majestic world." --Shak. "She might have forsaken him if he had not got the start of her." --Dryden. [1913 Webster]