Explore "twenty": its Old English roots defining "two tens." This entry covers meanings (number, decade, currency), diverse examples, and common idioms for this cardinal number.

Explore "two": its ancient Indo-European roots defining the cardinal number. This entry covers meanings (quantity, pair, time), diverse examples, and common idioms for this fundamental numerical term.

Explore "math/maths": its Ancient Greek roots defining knowledge and study. This entry covers meanings (academic field, calculations), diverse examples, and common idioms for this fundamental discipline.