necessary, requisite, compulsory, necessary, indispensable, incumbent, important

bow with an iron chain with which athletes exercise

necessity, requisiteness, compulsion, adherence

consider necessary or right, deem indispensable

closely related to each other, reciprocated (or intimate) friendship, reciprocal, reciprocated, correlative, inseparable

declaring an inessential thing to be indispensable

become necessary, be incumbent (on)

to be or become necessary (for), to follow of necessity, to be incumbent (on), to behove

make (something) incumbent or obligatory (on)

closely related to each other, reciprocated (or intimate) friendship, reciprocal, reciprocated, correlative, inseparable

from one thought to the other

unavoidable, compulsory, incumbent

binding, essential

beyond time, timeless

essentially

Library: difference or objectionable sentence, or sign of missing letter or word

auspicious arrival or coming

a good turn repaid by evil

intransitive verb