Green’s Dictionary of Slang

1. the captain.

1740		Scots Mag. 8 Feb. n.p.: To honest John, who made a leg: ‘Ah! honest Skip,’ said he. And Skip was well content with that.
1856		C. Abbey diary 6 Sept. in Gosnell Before the Mast (1989) 69: ‘Port fore brace quick’ said the ‘Skip’ & ‘box’ her off, but no she got all ‘buggered’ up main sail & all the courses full & topsails & all the rest aback.
1901		Boy’s Own Paper 22 June 598: The leaders of the expedition dubbed the mate the ‘Skipper,’ soon after shortening it into ‘Skip’.
1946		G. Gibson Enemy Coast Ahead (1955) 220: There she is, skip.

2. (US prison) a jailer.

1929

A.J. Barr Let Tomorrow Come 73: Maybe you think skip don’t know that.

3. as a term of address, esp. to a boss, a manager, a barman etc.

1966		C. Wood Fill the Stage With Happy Hours (1967) Act VI: One for the road skip?
1973		(con. 1930s) F. Huelin Keep Moving 5: We’ll work our passage, skip.
1987		(con. 1967) E. Spencer Welcome to Vietnam (1989) 122: ‘They’re asking for you, Skip,’ he says.
2001		(con. 1981) A. Wheatle East of Acre Lane 141: Alright, skip, you’re safe. Follow me.
2017		V. McDermid Insidious Intent (2018) 69: ‘The thrill of the chase, skip. You can’t beat it’.