obligeyoudaoicibaDictYouDict
oblige: [13] To oblige someone is etymologically to ‘bind them to’ something with a promise. The word comes via Old French obliger from Latin obligāre, a compound verb formed from the prefix ob- ‘to’ and ligāre ‘tie’ (source of English liable, ligament, etc). By classical times its original literal sense had been extended figuratively to ‘make liable, put under an obligation’. The synonymous obligate [16] comes from its past participial stem, as does obligatory [15].
=> liable, ligament, obligatory
oblige (v.)youdaoicibaDictYouDict
c. 1300, "to bind by oath," from Old French obligier "engage one's faith, commit (oneself), pledge" (13c.), from Latin obligare "to bind, bind up, bandage," figuratively "put under obligation," from ob "to" (see ob-) + ligare "to bind," from PIE root *leig- "to bind" (see ligament). Main modern meaning "to make (someone) indebted by conferring a benefit or kindness" is from 1560s. Related: obliged; obliging.