The verb bear has very deep, tenacious roots. It was beran in Old English, and this in turn was a development from an Indo-European root which already had the dual meanings of ‘carry’ and ‘give birth‘.
One word related to the ‘carry’ meaning is burden, which is literally something heavy that has to be carried, but which is more often used metaphorically to refer to responsibilities, obligations, difficulties etc. which have to be ‘carried’ – e.g. ‘the tax burden on small breweries’. Burden is also used as a verb in these metaphorical meanings – e.g. ‘I’m sorry to burden you with all my problems’. Bear itself (plus bearable and unbearable) is also used in many phrases related to being overburdened with difficult or unpleasant ideas or situations – e.g. ‘I could hardly bear to look’, ‘I can’t bear the thought of starting all over again’, ‘It was more than I could bear‘.
Fertile (plus fer’tility, ‘fertilize, ‘fertilizer and fertili’zation) is derived from Latin ferre (‘carry’), which is cognate with bear. (You can see the same alternation between Germanic b and Latin f in brother and fraternal, or in break and fraction/fracture.) Fertile means ‘bearing or producing in abundance’, whether it be offspring, crops (e.g. fertile soil) or ideas (e.g. a fertile imagination).
To suffer is, etymologically, to ‘carry or hold up from underneath’ (sub + ferre) and, like bear, its meaning has been extended to the idea of enduring something unpleasant, painful or difficult as if it was a physical burden – e.g. to suffer from depression, to suffer a defeat, to suffer from unemployment. Someone or something extremely unpleasant or annoying can be described as insufferable or unbearable – e.g. an insufferable bore, unbearable heat (unbearably hot weather) – as if it is a burden too heavy to carry.
The ‘give birth‘ meaning of bear appears most often in the passive – e.g. ‘I was born on a Sunday’. Apart from birth itself, another word related to the ‘give birth‘ meaning of ‘bear‘ is bairn (‘child’), now mostly used in Scotland but formerly more widespread.
The differentiation between the two spellings of the past participle of bear – born for the ‘give birth‘ meaning and borne for the ‘carry’ meaning – only became established in the early 17th century.
The noun bear is unrelated to the verb. It originally meant a ‘brown animal’, or perhaps a more vaguely dark-coloured one; in any case the name was obviously given by people who had never seen polar bears!
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