Green’s Dictionary of Slang

lark n.3

[? northern dial. lake, to play (its Yorks. pron. might well have sounded more like ‘lark’) or SE skylark, to play tricks, to indulge in rough horseplay]

1. [19C+] a frolic, a game; thus larkiness, a propensity for such pleasures; also used ironically/negatively.

2. [early 19C] a propensity for fun and games.

3. [mid-19C] the butt of a joke or ‘game’.

4. [mid-19C; 1970s] (also larkey) an amusing person.

5. [mid-19C+] any form of activity, occupation.

6. [1920s+] (also larks) a criminal scheme.

In derivatives

larkishness (n.)

[mid-19C] playfulness.

In compounds

lark rig (n.) [rig n.2 (1)]

[late 18C] (UK Und.) a confidence trick.

In phrases

and no larks

[1910s] and no fooling around.

come half-larks with (v.)

[1910s–20s] to deceive, to fool.

kick up a lark (v.) [kick up v.]

[early–mid-19C] to cause a commotion.

on a lark

[early 19C–1920s] on a spree.

on the lark (also upon the lark)

[early–mid-19C] having fun.