dependable
direct
reliable
accordant
alike
arrowlike
automatic
balanced
changeless
close
consistent
consonant
constant
continuous
correspondent
dead straight
delicate
equable
equal
even
exact
express
faithful
fine
flat
homogeneous
horizontal
immediate
immutable
in a line
incommutable
inconvertible
indefeasible
inerrable
inerrant
inert
infallible
insusceptible of change
intransmutable
invariable
irretrievable
irreversible
irrevocable
lasting
level
lineal
linear
mathematical
measured
mechanical
methodic
inexorable
inviolable
painstaking
punctilious
scrupulous
staunch
steadfast
unalterable
unbending
unchanging
unerring
unfailing
unflagging
unflinching
unhesitating
unhurried
unquestioned
unshaken
unshrinking
unswerving
unvaried