twig

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A young shoot representing the current season's growth of a woody plant.
2. n. Any small, leafless branch of a woody plant.
3. v. To observe or notice.
4. v. To understand or figure out: "The layman has twigged what the strategist twigged almost two decades ago” ( Manchester Guardian Weekly).
5. v. To be or become aware of the situation; understand: "As Europe is now twigging, the best breeding ground for innovators who know how to do business is often big, competitive companies” ( Economist).
6. n. Chiefly British The current style; the fashion.

Century Dictionary and Cyclopedia

1. n. In anatomy, one of the minute branches of a blood-vessel.
2. n. A small shoot of a tree or other plant; a small branch; a spray.
3. n. A divining-rod.
4. n. In ceramics, a thin strip of prepared clay used in modeling a pottery vessel, especially in the imitation basket work common in Leeds pottery.
5. To switch; beat.
6. To be vigorous or active; be energetic
7. To twitch; jerk.
8. n. A twitch; a jerk; a quick, sudden pull.
9. To notice; observe narrowly; watch.
10. To comprehend; understand; perceive; discover.
11. To understand; see; “catch on.

Wiktionary

1. n. A small thin branch of a tree or bush.
2. v. transitive To beat with twigs.
3. v. colloquial, regional To realise something; to 'catch on'.

GNU Webster's 1913

1. v. Obs. or Scot. To twitch; to pull; to tweak.
2. v. colloq. To understand the meaning of; to comprehend; as, do you twig me?
3. v. To observe slyly; also, to perceive; to discover.
4. n. A small shoot or branch of a tree or other plant, of no definite length or size.
5. v. To beat with twigs.

WordNet 3.0

1. v. branch out in a twiglike manner
2. n. a small branch or division of a branch (especially a terminal division); usually applied to branches of the current or preceding year
3. v. understand, usually after some initial difficulty