Note: Although there are other interpreted programming languages that have been written for, or ported to, DOS; those offered here are ones that are, compatibility wise, better suited to the DOS OS.
If undecided on an interpreted language, try the built-in Batch File language. Alternatively consider the line-numbered GW-BASIC (even though it was bundled with DOS, avoid the QuickBasic structured language interpreter).

BASIC (line-numbered)

GW-BASIC (ver 3.22) - Abandonware

Common LISP

Star Sapphire Common LISP (ver 3.4) - Shareware made Abandoned Freeware - {unsetup}

DIGITAL Command Language

µDCL (ver 0.1) - Abandoned Freeware

FORTH

mina ciforth (ver 4.0.6) - Abandoned Freeware

JavaScript

DOJS (ver 1.13.0) - Freeware - {unsetup}
~ CWSDPMI (ver 0.90+ r7)

~ [CSDPMI7B .zip]

Perl

BigPerl (ver 4.0pl36) - Abandoned Freeware

PILOT

PILOT (ver unknown) - Abandonware

Rexx

Regina Rexx (ver 3.9.5) - Freeware
~ DOS/4G (ver 2.61)

~ [DOS4G .zip]

Tcl

Tcl (ver 7.3) - Abandoned Freeware - {unsetup}

Command-Subset Interpreters - (These interpreters only include a DOS suitable subset of the languages full command set)

Lua

Lua (ver 5.2.2) - Abandoned Freeware
~ CWSDPMI (ver 7)

~ [CSDPMI7B .zip]

Python

Python (ver 1.2) - Abandoned Freeware

Ruby

Ruby (ver 1.8.4) - Abandoned Freeware - {unsetup}

Runtime Engines - (These are read-only interpreters)

Btrieve Runtime

Btrieve Record Manager (ver 5.10a) - Abandoned Freeware

QuickBASIC Runtime

QuickBASIC Compiler Runtime (ver 4.50) - Abandoned Freeware