Ok then, seeing as you asked. In the OED there are 10 meanings of the word Paddy. See (1) for main meaning (i.e. Paddy) and 4 for paddy as in temper - derived from Irishman, and labelled 'derogatory'
1. colloquial. Now potentially offensive.
Usually in form Paddy. An Irishman.
Frequently used as a derogatory form of address.
1.b.
1809–
to come (the) paddy over: to dupe or hoodwink, by means of the supposed Irish talent for flattery or persuasive talk (cf. blarney n.).
1.c.
1925–
In form Paddy. A proprietary name for: an Irish whiskey. Hence more widely (also paddy): any Irish whiskey. Also: a drink of this.
2.
1856–
colloquial. A bricklayer's or builder's labourer or assistant
3.
1876–
English regional. = Paddywatch n. Now rare
4.
1888–
U.S. colloquial. In form Paddy. The ruddy duck, Oxyura jamaicensis. Cf. paddywhack n.2. Now rare.
5.
1894–
colloquial. A fit of temper, a rage; a hot temper. Esp. in in a paddy. Cf. paddywhack n. 4
Paddywhack
1.a.
1773–
Chiefly derogatory. An Irishman.
6.
1895–
A type of drill with expanding cutters (see quot. 1895).
7.
1927–
Railways slang. A train for conveying coal from a pithead. Now historical.
8.
1945–
slang. Also Paddy. Originally and chiefly in African American usage; also among Hispanic Americans: a white person