(un-, prefix1 affix 2.)

Not subjected to straining or stretching; free from strain. Also figurative.

(un-, prefix1 affix 2.)

Of a person, the mind, the conscience, etc.: untroubled; free from agitation or anxiety.

Not subjected to trouble or disquiet.

Free from care, apprehension, or anxiety; carefree, untroubled. Formerly frequently in negative sense… In predicative use.

(un-, prefix1 affix 2b)

Not plagued; untormented; unburdened.

Not oppressed; esp. free from oppressive influences.

Without care or concern: (a) not bestowing care; careless, negligent, heedless; (b) free from care or apprehension; not anxious, untroubled; (constr…

Chiefly with of, †for. Free from fear of or about something; without anxiety for. Also with clause as complement. Now rare.

(un-, prefix1 affix 2.)

In extended use: unobscured; undimmed; (of the mind or thoughts) clear. Also of the conscience, facial expression, etc.: free from trouble or unease.

Not afflicted with pangs; not characterized by pain.

Not disturbed; undisturbed.

Without pain or suffering; not causing, afflicted with, or expressive of pain or distress.

(un-, prefix1 affix 2.)

Free from disturbance or excitement.

Not haunted by (or of) something.

(un-, prefix1 affix 2.)

Not disconcerted; untroubled, unperturbed.

all serene: slang phrase for ‘all's well’, ‘all right’. Also jocularly all sereno.

Of a person, or his or her behaviour, etc. Not agitated or worried; calm, unruffled.

(un-, prefix1 affix 2b affix 2c; cf. throw, v.1 38.)

Of a person: comfortable, at ease, content, satisfied; reasonable, understanding. Usually with about, with.