Yb n 1: a soft silvery metallic element; a rare earth of the lanthanide series; it occurs in gadolinite and monazite and xenotime [syn: {ytterbium}, {Yb}, {atomic number 70}] 2: a unit of information equal to 1000 zettabits or 10^24 bits [syn: {yottabit}, {Ybit}, {Yb}] 3: a unit of information equal to 1000 zettabytes or 10^24 bytes [syn: {yottabyte}, {YB}] 4: a unit of information equal to 1024 zebibytes or 2^80 bytes [syn: {yottabyte}, {yobibyte}, {YB}, {YiB}]