letted the cat ouf the bag (verb) blurt: utter suddenly
Sinonime: changeless,
consistent,
constant,
fixed, immovable,
immutable, inalterable,
inflexible,
monotonous,
perpetual,
regular,
rigid,
same,
set,
static, unalterable, unchangeable,
unchanging, undiversified, unfailing,
uniform, unmodifiable, unrelieved, unvarying,
unwaveringAntonime: changeable,
changing,
variable,
varying