niggle

American Heritage® Dictionary of the English Language, Fourth Edition

1. v. To be preoccupied with trifles or petty details.
2. v. To find fault constantly and trivially; carp. See Synonyms at quibble.

Century Dictionary and Cyclopedia

1. To eat sparingly; nibble.
2. To act in a mincing manner; work in a finicking, fussy way.
3. To trifle; be employed in trifling or petty carping.
4. To fret; complain of trifles.
5. . To draw out unwillingly; squeeze out or hand out slyly.
6. To play with contemptuously; make sport or game of; mock; deceive.
7. To fill with excess of details; over-elaborate.
8. n. Small cramped handwriting; a scribble; a scrawl.

Wiktionary

1. n. A minor complaint or problem.
2. n. obsolete Small, cramped handwriting.
3. v. To trifle with; to deceive; to mock.
4. v. To dwell too much on minor points.
5. v. To fidget, fiddle, be restless.

GNU Webster's 1913

1. v. obsolete To trifle with; to deceive; to mock.
2. v. To trifle or play.
3. v. Prov. Eng. To act or walk mincingly.
4. v. Prov. Eng. To fret and snarl about trifles.
5. v. To move about restlessly or without result; to fidget.
6. v. To be finicky or excessively critical; to potter; esp., to work with excessive care for trifling details, as in painting.
7. v. To use, spend, or do in a petty or trifling manner.
8. v. To elaborate excessively, as in art.

WordNet 3.0

1. v. argue over petty things
2. v. worry unnecessarily or excessively