plum, plumb Definition

plum
noun

1. Any of a number of varieties of shrub or small tree, cultivated in temperate regions for its edible fruit, or for its ornamental flowers or foliage.
2. The smooth-skinned red, purple, green or yellow fruit of this tree, which has a hard central stone surrounded by sweet juicy flesh, eg damson, greengage.
3. A raisin used in cakes, etc.

Example: plum pudding
4a. colloq
Something especially valued or sought;
4b. as adj.

Example: a plum job
5. A deep dark-red colour.

adj

1. Plum-coloured. See also plummy.

Etymology: Anglo-Saxon plume: from Greek proumnon, from proumne plum-tree.

Info:

These words are sometimes confused with each other.