today, this day / nowadays

one day, 24 hours / the daytime, the period from dawn until dusk / (figuratively) a short period of time / one day, someday, an unspecified day / the first day of the month

strontium, Sr

Kyūjitai form of 中華民国: Republic of China.

(formal) dear sirs, Messrs. (form of address used in formal letters, placed after the name of the organization to address members of that organization)

(linear algebra) transposed matrix

the Republic of China

transmission, a gearbox (a mechanical assembly of gears that changes the torque and speed of shaft rotations)

horizon on land

brain (person providing intelligence)