We all love a bit of etymology, don't we? Like this, for example:
Middle English ethimologie, from Anglo-French, from Latin etymologia, from Greek, from etymon + –logia –logy
1398, from Gk. etymologia, from etymon 'true sense' (neut. of etymos 'true', related to eteos 'true') + logos 'word'.
Or here's another pertinent one:
Middle French carriere, from Old Occitan carriera 'street', from Medieval Latin carraria 'road for vehicles', from Latin carrus 'car'.
c.1534, 'a running course' (especially of the sun, etc., across the sky), from M.Fr. carriere 'road, racecourse,' from O.Prov. carriera, from V.L. *(via) cararia 'carriage (road), track for wheeled vehicles,' from L. carrus 'chariot'. Sense of 'course of a working life' first attested 1803.
So, we may conclude that, in the olden days (ie. pre-Industrial Revolution), people just sort of trundled along – there was no need of a word to describe 'a vocational choice, consuming one's working life' cos life just didn't work like that. It's only since 1803 that we've had to have this word, which I find quite a shame. I prefer trundling.