surface-to-underwater

[ sur-fis-too-uhn-der-waw-ter, -wot-er ]
/ ˈsɜr fɪs tuˈʌn dərˌwɔ tər, -ˌwɒt ər /

adjective

(of a missile, message, etc.) traveling from the surface of the earth to a target underwater.

adverb

from the surface of the earth to a target underwater.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019