📘 English Definition（英文释义）
- n. A genus of large edentulous sirenians, allied to the dugong
- and manatee, including but one species (R. Stelleri); -- called also
- Steller's sea cow.
- S () the nineteenth letter of the English alphabet, is a consonant, and
- is often called a sibilant, in allusion to its hissing sound. It has
- two principal sounds; one a mere hissing, as in sack, this; the other a
- vocal hissing (the same as that of z), as in is, wise. Besides these it
- sometimes has the sounds of sh and zh, as in sure, measure. It
- generally has its hissing sound at the beginning of words, but in the
- middle and at the end of words its sound is determined by usage. In a
- few words it is silent, as in isle, debris. With the letter h it forms
- the digraph sh. See Guide to pronunciation, // 255-261.