how can i know the meaning of some terms in opcode

[Vinayakamk]

hi,
i just wanted to know the terms like e.g c_nzimm10hi in instruction c.addi16sp
i have resources that tells function of c.addi16sp ,but i wanted to know such terms to understand the opcode
kindly share the resources or any material that explains me,
"rv_c": [
"c.addi16sp c_nzimm10hi c_nzimm10lo 1..0=1 15..13=3 11..7=2",
"c.addi4spn rd_p c_nzuimm10 1..0=0 15..13=0",
"c.addi rd_rs1_n0 c_nzimm6lo c_nzimm6hi 1..0=1 15..13=0",
"c.li rd_n0 c_imm6lo c_imm6hi 1..0=1 15..13=2", ...]

i exposed to this for the first time,sorry if i dint noticed if those things are defined elsewhere