Tar-Telperiën's name is in Quenya. It is difficult to translate exactly; it appears to be a feminization of Telperion, one of the Two Trees of Valinor. Alternatively, her name could mean "Silver One" (from tyelpë 'silver' and -iën, a feminine ending). Like all the rulers of Númenor who took their royal titles in Quenya, Telperiën added the suffix tar- ('high') to her name when she received the Sceptre.
Quenya
telperien
feminine name. Telperien
Tar-Telperiën
Tar-Telperiën
Tar-Telperien was the 10th ruler of Númenor and the second ruling queen (LotR/1035, UT/220). The first element of her name is likely to be telpë “silver”. The second element is less clear: it could be a variant of the feminine suffix -ien, or some later iteration of ᴹ✶rīʒende “queen = crowned lady” (hat-tip to Vyacheslav Stepanov for the second suggestion).