Castellano lentecer-relentecer vs English relent

jose

Castellano relentecer y lentecer:
relentecer. (Del lat. relentescĕre, ablandarse).
1.intr. Dicho de una cosa: ablandarse (ǁ ponerse blanda). U. t. c. prnl. ¶ MORF. conjug. c. agradecer.
2.Lentecer, ablandar o reblandecer una cosa.

lentecer. (Del lat. lentescĕre).
intr. p. us. Dicho de una cosa: Ablandarse o reblandecerse. U. t. c. prnl. ¶ MORF. conjug. c. agradecer.
But, it seems, both of these two words are used so rarely.
May we should use These Sinónimos instead.
Sinónimos: ablandar, suavizar, blandear, emblandecer, enmollecer, reblandecer.
Antónimo: endurecer.



English relent:
relent.
verb.
1. to finally agree to sth after refusing
   SYN  give in :
   'Well, just for a little while then,' she said, finally relenting.
2. to become less determined, strong, etc.
   After ten days the rain relented.
     The police will not relent in their fight against crime.

more examples:
......is unlikely to relent on issues such as intellectual property...