Generally, it means the tech (currently) possessed by your race. If you choose a TN start, and have Aurora choose your starting tech, you'll almost always end up with some things you wouldn't personally have chosen. To prevent one's empires becoming cookie-cutter clones always pursuing the saem technology in the same order, many people prefer to let Aurora 'jump start' them towards a build philosophy.
In several cases 'racial tech' is used to mean the specific design of a component actually designed, researched and built by your race. For example, Lasers come in 10cm, 12cm, 15cm, 20cm, 25cm, etc. sizes, Infrared, Visible, Near Ultraviolet, Far Ultraviolet, etc. wavelengths, with 1-, 2-, 3-, 4-, 5-, 6-, 8-, 10-unit power capacitors and in full size, 90%, 80%, 75% 67%, 50% etc. reduced sizes. Combining your choices for focal length, wavelength, capacitor recharge rate, and size reduction is 'designing your racial tech', which is then researched as a project before you can build the specific laser that is now part of your 'racial tech'.
My 'racial tech' might include 10cm IR C1 (the first lasers I ever built), 12cm vislight C2 (my first upgrade), 10cm vislight C3 (first gen PD), 12cm NUV C4 (second gen PD) and 20cm FUV C5 (my battleline's 'heavy guns'). Somebody else's racial tech might be 10cm NUV C3 50% size lasers, since they've chosen to only build lasers for their fighters, and use missles & gauss cannon for their ships.