soft (adv.) 1
[used as a command] not so fast, wait a moment
1H4 II.i.37 [First Carrier to Gadshill] Nay, by God, soft!
AC II.ii.87 [Lepidus to Caesar] Soft, Caesar!
Ham III.i.88 [Hamlet alone] Soft you now, / The fair Ophelia!
MA V.i.196 [Don Pedro to Claudio] But, soft you, let me be
Oth V.ii.334 [Othello to all] Soft you; a word or two before you go
RJ I.i.195 [Benvolio to Romeo] Soft! I will go along
Tem I.ii.450 [Prospero to Ferdinand] Soft, sir! One word more
See also...
Attention signals