The following table lists the reserved keywords. Keywords marked with an asterisk (*) are reserved by Verilog and are not supported by Vivado synthesis.
| always | and | assign | automatic |
| begin | buf | bufif0 | bufif1 |
| case | casex | casez | cell* |
| cmos | config* | deassign | default |
| defparam | design* | disable | edge |
| else | end | endcase | endconfig* |
| endfunction | endgenerate | endmodule | endprimitive |
| endspecify | endtable | endtask | event |
| for | force | forever | fork |
| function | generate | genvar | highz0 |
| highz1 | if | ifnone | incdir* |
| include* | initial | inout | input |
| instance* | integer | join | larger |
| liblist* | library* | localparam | macromodule |
| medium | module | nand | negedge |
| nmos | nor | noshow-cancelled* | not |
| notif0 | notif1 | or | output |
| parameter | pmos | posedge | primitive |
| pull0 | pull1 | pullup* | pulldown* |
| pulsestyle_ondetect* | pulsestyle_onevent* | rcmos | real |
| realtime | reg | release | repeat |
| rnmos | rpmos | rtran | rtranif0 |
| rtranif1 | scalared | show-cancelled* | signed |
| small | specify | specpa | strong0 |
| strong1 | supply0 | supply1 | table |
| task | time | tran | tranif0 |
| tranif1 | tri | tri0 | tri1 |
| triand | trior | trireg | use* |
| vectored | wait | wand | weak0 |
| weak1 | while | wire | wor |
| xnor | xor |