opaque, a. intransparent; (Colloq.) [obscure], unintelligible.
open, a. accessible, [clear], unobstructed, [unrestricted]; ajar, unlocked; extended, expanded, [spread], [gaping], [yawning], unfolded, dehiscent; [frank], [unreserved], [candid], ingenuous, [guileless], [overt], undisguised; [generous], [liberal], [bounteous], open-handed; revealed, [patent], [manifest]; [unsettled], [undetermined], [debatable], [undecided], controvertible; [mild], clement; [free], disengaged, unappropriated, unemployed.
open, v. [spread], [expand], [unfold], evolve; [reveal], disclose; unclose, unlock, unfasten; [begin], [commence]; dehisce.
open-air, a. outdoor, al-fresco.
opening, a. [beginning], [introductory], initiatory, preliminary.
opening, n. aperture, fissure, [gap], orifice, [rift], [chasm], hiatus, [rent]; [beginning], [introduction], outset; vacancy.
openly, adv. publicly, unreservedly, candidly.
open-mouthed, a. [gaping], [yawning]; [greedy], [clamorous], [ravenous], [rapacious], eager.
opiate, n. [narcotic], anodyne, [sedative], dormitive, soporific.
opiate, a. somniferous, [narcotic], anodyne, [sedative], soporiferous, dormitive.