Emily Dickinson Lexicon

FAST, a.¹ [Sax. fæst, fest; G. fest; D. vast; Sw. and Dan. fast; from pressing, binding. Qu. Pers. بَسْتَنْ bastan, to bind, to make close or fast, to shut, to stop; Ir. fosadh, or fos, a stop. See Class Bz, No. 24, 35, 41, 60, 66, 86.]

1. Literally, set, stopped, fixed, or pressed close. Hence, close; tight; as, make fast the door; take fast hold.
2. Firm; Immovable. Who, by his strength, setteth fast the mountains. Ps. lxv.
3. Close; strong. Robbers and outlaws – lurking in woods and fast places. Spenser.
4. Firmly fixed; closely adhering; as, to stick fast in mire; to make fast a rope.
5. Close, as sleep; deep; sound; as, a fast sleep. Shak.
6. Firm in adherence; as, a fast friend. Fast and loose, variable; inconstant; as, to play fast and loose.