ANSWER: I assume you mean the English word. The name “Jehovah” is the most recent anglicized expression of the Hebrew Tetragrammaton – YHWH. According to the online user-edited encyclopedia, Wikipedia, the name in its recognizable present form did not come about until as recently as 400 years ago. That is because the word was originally spelled with an “I” instead of a “J”.
The name of God appeared as “Iehouah” in the very first English translation from the Hebrew, translated by William Tyndale and published in 1525. And the King James Bible, published in 1611, originally rendered the divine name as Iehovah. The reason it was spelled with an “I” is because that is how it appeared in Latin and the letter “J” had not been distinguished from the letter “I” at that time. Also, the letter “V” was not known in Old English.
So, just as the English language has gone through a developmental evolution over the centuries (no doubt as have all languages), so too the word “Jehovah” has undergone several revisions.
What is important is not the spelling or pronunciation, but that English-speaking people recognize that “Jehovah” is the most widely used and accepted form of the personal name of God – distinguishing him from all others, including Jesus.
Below is a list copied from an online Watchtower publication of how the YHWH is rendered in various languages.
IEHOVA: Gilbertese; Hawaiian; Hiri Motu; Kerewo; Kiwai; Marquesas; Motu; Panaieti (Misima); Rarotongan; Tahitian; Toaripi
IEOVA: Kuanua; Wedau
IOVA: Malekula (Kuliviu); Malekula (Pangkumu); Malekula (Uripiv)
JEHOBA: Kipsigis; Mentawai
JEHOVA: Croatian; German; Kélé (Gabon); Lele (Manus Island); Nandi; Nauruan; Nukuoro
JEHÔVA: Fang; Tsimihety
JEHOVAH: Dutch; Efik; English; Kalenjin; Malagasy; Narrinyeri; Ojibwa
JEOVA: Kusaie (Kosraean)
JIHOVA: Naga (Angami); Naga (Konyak); Naga (Lotha); Naga (Mao); Naga (Ntenyi); Naga (Sangtam); Rotuman
JIWHEYẸWHE: Gu (Alada)
YAWE: Bobangi; Bolia; Dholuo; Lingala; Mongo (Lolo); (Lo)Ngandu; (Lo)Ntumba; (Ke)Sengele
YEHOFA: Southern Sotho
YEHOVA: Chokwe; Chuana (Tlapi); (Ki)Kalanga; Logo; Luba; Lugbara; (Chi)Luimbi; (Chi)Lunda (Ndembu); (Chi)Luvale; Santo (Hog Harbor); Tiv; Umbundu; (Isi)Xhosa
YEHOVAH: Bube; Mohawk; Nguna (Efate); Nguna (Tongoa)
YEHOWA: Ga; Laotian; (Ki)Songe; Tshiluba
YEOBA: Kuba (Inkongo)
ZAHOVA: Chin (Haka-Lai)