S

S spherical lens; serine; siemens; substrate; sulfur; Svedberg unit; sacral vertebrae (S1–S5); heart sound (S1–S4).

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S /S / entropy.

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s second.

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S

The symbol for the element sulfur.

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1. The Greek letter sigma. Entries beginning with this character are alphabetized under sigma.

2. The symbol for reflection coefficient.

3. The symbol for standard deviation.

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s

abbr.

1. Latin semis (half)

2. Latin sinister (left)

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S

chemical symbol, sulfur; symbol for siemens and svedberg; [L.] semis (half); sight; [L.] signa (mark); [L.] sinister (left).

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S phase

see cell cycle.