Green’s Dictionary of Slang

jism n.

also gism, gisum, gizzem, gizzum, gyss, gyssum, gysum, jiss, jissem, jissim, jissom, jiz, jizz, jizzum
[ety. unknown; note northeast US dial. jasm, energy]

1. [mid-19C+] (orig. US) energy, spirit; thus jizzless adj., apathetic.

2. [late 19C+] (orig. US) semen.

3. [1930s–40s] (US, mainly Southern) gravy.

4. [1990s+] (US) an ejaculation, lit. and fig. an emission.

5. (US prison) power, influence.

In compounds

jizzbag (n.) [1980s+]

1. a contraceptive sheath.

2. (also jizzball) a general term of abuse, also as a term of address; also attrib.

jizzbags (n.) [SE bag/bag n.1 (1)]

[1990s+] the testicles.

jizzrag (n.) (also jiz rag)

[1990s+] a handkerchief or similar piece of material into which one masturbates.

jizz rocket (n.)

[2000s] (US) the penis.

jizztrumpet (n.)

(2010s) general term of abuse, underpinned by idea of talking nonsense.

jizzwater (n.)

[2000s] semen.

In phrases

lick someone’s jizz (v.)

[1980s+] (US) to be impressed.