/plus/ , prep.
1. more by the addition of; increased by: ten plus two is twelve.
2. with the addition of; with: He had wealth plus fame.
adj.
3. involving or noting addition.
4. positive: a plus quantity.
5. more (by a certain amount).
6. Elect. pertaining to or characterized by positive electricity: the plus terminal.
7. Mycol. (in heterothallic fungi) designating, in the absence of morphological differentiation, one of the two strains of mycelia that unite in the sexual process.
8. having a certain quality to an unusual degree: He has personality plus.
n.
9. a plus quantity.
10. Arith. See plus sign .
11. something additional.
12. a surplus or gain.
conj.
13. Informal. also; and; furthermore: A bicycle is cheaper than a car, plus it doesn't pollute the air.
adv.
14. in addition; besides.
[ 1570-80; plus more; akin to Gk pleíon, ON fleiri more, OE feolu, fela, G viel, Goth filu, OIr il, Gk polý many ]
Usage . Since PLUS as a preposition has long had the meanings "more by the addition of" and "with the addition of," it was but a short step to a newer use, mainly in informal writing and speech, as a conjunction meaning "also, and, furthermore." Although this use is increasing, many object to it, and it is rare in more formal writing. AND PLUS is likewise objected to, especially for being redundant: The paper was delivered two hours late, and plus it was soaking wet.