PAINFUL

irritating, painful

(adjective) causing physical discomfort; “bites of black flies are more than irritating; they can be very painful”

atrocious, abominable, awful, dreadful, painful, terrible, unspeakable

(adjective) exceptionally bad or displeasing; “atrocious taste”; “abominable workmanship”; “an awful voice”; “dreadful manners”; “a painful performance”; “terrible handwriting”; “an unspeakable odor came sweeping into the room”

painful

(adjective) causing physical or psychological pain; “worked with painful slowness”

afflictive, painful, sore

(adjective) causing misery or pain or distress; “it was a sore trial to him”; “the painful process of growing up”

Source: WordNet® 3.1

Etymology

Adjective

painful (comparative painfuller or more painful, superlative most painful)

Causing pain or distress, either physical or mental. [from 14th c.]

Afflicted or suffering with pain (of a body part or, formerly, of a person). [from 15th c.]

Requiring effort or labor; difficult, laborious. [from 15th c.]

(now rare) Painstaking; careful; industrious. [from 16th c.]

(informal) Very bad, poor.

Synonyms

• (full of pain): doleful, sorrowful, smartful, irksome, annoying

• (requiring labor or toil): laborious, exerting

Antonyms

• (causing pain): painless, painfree

Source: Wiktionary

Pain"ful, a.

1. Full of pain; causing uneasiness or distress, either physical or mental; afflictive; disquieting; distressing Addison.

2. Requiring labor or toil; difficult; executed with laborious effort; as a painful service; a painful march.

3. Painstaking; careful; industrious. [Obs.] Fuller. A very painful person, and a great clerk. Jer. Taylor. Nor must the painful husbandman be tired. Dryden.

Syn.

– Disquieting; troublesome; afflictive; distressing; grievous; laborious; toilsome; difficult; arduous.

– Pain"ful*ly, adv.

– Pain"ful*ness, n.

Source: Webster’s Unabridged Dictionary 1913 Edition