than
conj.used to compare two things or people. You use it when the first thing has more or less of a quality than the second one.
conj.used to introduce the second element in a comparison. Functions as a subordinator following comparative adjectives or adverbs.
“She is taller than her brother.”
“The new office is much closer to the train station than the old one was.”
“While the initial investment was higher than we anticipated, the long-term savings on energy costs more than justified the expenditure over the first three years.”
Used after comparative adjectives (ending in -er or with 'more') and certain words like 'rather' or 'other'.
than vs then — Then indicates a point in time or a sequence of events, while than introduces the second part of a comparison.
Learners often confuse 'than' (comparison) with 'then' (time).
From Middle English than, thanne, from Old English þanne, a variant of þonne (“then, since, because”), from Proto-West Germanic þan, from Proto-Germanic þan (“at that, at that time, then”), from earlier þam, from Proto-Indo-European tóm, accusative masculine of *só (“demonstrative pronoun, that”). Cognate with Dutch dan (“than”), German denn (“than”), German dann (“then”). Doublet of then.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.