precarious, shaky, fragile, uncertain, uneasy, dicey, perilous, inextricable, iffy, fractious, tense, unstable, murky, frayed, untenable, dire, sketchy, bleak, rocky, weak, dubious, nebulous, strained, unsettled, testy, troubling, hazy, fleeting, illusory, debatable, problematical, improbable, implausible, ephemeral, tight, ambivalent, muddled, wobbly, problematic, fortuitous, unlikely, cemented, crucial, uneven, inescapable, faltering, imperfect, pessimistic, patchy, spotty, intractably, brittle, difficult, unforthcoming, impermanent, unshakable, unpredictable, chaotic, awkward, frostier, ominous, slim, ambiguous, paradoxical, grim, worrisome, plausible, assailable, turbulent, bumpy, undeniable, questionable, peculiar, flimsy, dysfunctional, unpromising, distant, volatile, delicate, tricky, doubtful, acrimonious, touchy, skittish, deadlocked, elusive, optimistic, equivocal, parlous, sanguine, jittery, contradictory, nonexistent, inconsistent, threadbare, scant, contentious, bizarre, hopeless, eroded, unshakeable, skeptical, firmer, secure, ontological, strengthened, stronger, insecure, insubstantial, flimsiest, looser, ontic, slenderest, tenable, unchallengeable

lens capsule, tenuously

fine, slight, thin